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Development Of Conditioning And Test Method For Assessment of Durability of FRC Exposed To Severe Environments

Permanent Link: http://ufdc.ufl.edu/UFE0024858/00001

Material Information

Title: Development Of Conditioning And Test Method For Assessment of Durability of FRC Exposed To Severe Environments
Physical Description: 1 online resource (253 p.)
Language: english
Creator: Kim, Byoung
Publisher: University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: 2009

Subjects

Subjects / Keywords: conditioning, crack, degradation, durability, frc, idt, toughness
Civil and Coastal Engineering -- Dissertations, Academic -- UF
Genre: Civil Engineering thesis, Ph.D.
bibliography   ( marcgt )
theses   ( marcgt )
government publication (state, provincial, terriorial, dependent)   ( marcgt )
born-digital   ( sobekcm )
Electronic Thesis or Dissertation

Notes

Abstract: An experimental program was performed to evaluate durability of FRC produced with four fiber types (polypropylene/PP, polyvinyl-alcohol/PVA, hooked-end steel/St, and cellulose/Cell). The effect of cellulose could not be evaluated because good fiber distribution was not achieved in laboratory mixing. Transport properties indicated that the addition of fibers to concrete improved the resistance of mass transport of deleterious materials; steel fibers were best. Fibers provided for post-cracking resistance; again, steel fibers were best. FRC beams produced with two concrete classes were subjected to simulated saltwater (immersed and wet/dry) and swamp (acid) environments for 27 months. Effect of fibers on durability could not be assessed reliably based on test results from either average residual strength (ASTM C1399) or flexural performance tests (ASTM C1609) because of non-uniform degradation and stress/strain distributions, as well as development of multiple cracks. Indirect tension testing (IDT) was identified as a more effective approach to achieve a uniformly-degraded cross-section and uniform stress/strain distribution. FRC specimens were subjected to an additional six months of saltwater conditioning, after which cracking and post-cracking behavior was assessed with IDT using testing and data interpretation procedures specifically designed to capture the effects of fibers. Test results indicated that PP fibers had the best resistance to saltwater environments (immersed and wet/dry), while PVA fibers had the worst, and resistance of steel fibers was somewhere between these two. However, steel fibers did not do well in fully immersed environments, but showed little or no degradation in wet/dry environments. The detrimental effect of acetic acid on aggregate and cement overwhelmed the degradation mechanism in swamp water, so the effect of fibers could not be distinguished for this environment. It was concluded that PP has the best durability for non-structural applications in saltwater environments. Steel may be suitable in non-submerged saltwater environments, particularly for structural applications, but should not be used if it will be in direct contact with reinforcing bars because it was found to accelerate corrosion of the bars. PVA should not be used in saltwater environments. Finally, it was concluded that transport properties alone are not necessarily good indicators of resistance to degradation.
General Note: In the series University of Florida Digital Collections.
General Note: Includes vita.
Bibliography: Includes bibliographical references.
Source of Description: Description based on online resource; title from PDF title page.
Source of Description: This bibliographic record is available under the Creative Commons CC0 public domain dedication. The University of Florida Libraries, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.
Statement of Responsibility: by Byoung Kim.
Thesis: Thesis (Ph.D.)--University of Florida, 2009.
Local: Adviser: Roque, Reynaldo.

Record Information

Source Institution: UFRGP
Rights Management: Applicable rights reserved.
Classification: lcc - LD1780 2009
System ID: UFE0024858:00001

Permanent Link: http://ufdc.ufl.edu/UFE0024858/00001

Material Information

Title: Development Of Conditioning And Test Method For Assessment of Durability of FRC Exposed To Severe Environments
Physical Description: 1 online resource (253 p.)
Language: english
Creator: Kim, Byoung
Publisher: University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: 2009

Subjects

Subjects / Keywords: conditioning, crack, degradation, durability, frc, idt, toughness
Civil and Coastal Engineering -- Dissertations, Academic -- UF
Genre: Civil Engineering thesis, Ph.D.
bibliography   ( marcgt )
theses   ( marcgt )
government publication (state, provincial, terriorial, dependent)   ( marcgt )
born-digital   ( sobekcm )
Electronic Thesis or Dissertation

Notes

Abstract: An experimental program was performed to evaluate durability of FRC produced with four fiber types (polypropylene/PP, polyvinyl-alcohol/PVA, hooked-end steel/St, and cellulose/Cell). The effect of cellulose could not be evaluated because good fiber distribution was not achieved in laboratory mixing. Transport properties indicated that the addition of fibers to concrete improved the resistance of mass transport of deleterious materials; steel fibers were best. Fibers provided for post-cracking resistance; again, steel fibers were best. FRC beams produced with two concrete classes were subjected to simulated saltwater (immersed and wet/dry) and swamp (acid) environments for 27 months. Effect of fibers on durability could not be assessed reliably based on test results from either average residual strength (ASTM C1399) or flexural performance tests (ASTM C1609) because of non-uniform degradation and stress/strain distributions, as well as development of multiple cracks. Indirect tension testing (IDT) was identified as a more effective approach to achieve a uniformly-degraded cross-section and uniform stress/strain distribution. FRC specimens were subjected to an additional six months of saltwater conditioning, after which cracking and post-cracking behavior was assessed with IDT using testing and data interpretation procedures specifically designed to capture the effects of fibers. Test results indicated that PP fibers had the best resistance to saltwater environments (immersed and wet/dry), while PVA fibers had the worst, and resistance of steel fibers was somewhere between these two. However, steel fibers did not do well in fully immersed environments, but showed little or no degradation in wet/dry environments. The detrimental effect of acetic acid on aggregate and cement overwhelmed the degradation mechanism in swamp water, so the effect of fibers could not be distinguished for this environment. It was concluded that PP has the best durability for non-structural applications in saltwater environments. Steel may be suitable in non-submerged saltwater environments, particularly for structural applications, but should not be used if it will be in direct contact with reinforcing bars because it was found to accelerate corrosion of the bars. PVA should not be used in saltwater environments. Finally, it was concluded that transport properties alone are not necessarily good indicators of resistance to degradation.
General Note: In the series University of Florida Digital Collections.
General Note: Includes vita.
Bibliography: Includes bibliographical references.
Source of Description: Description based on online resource; title from PDF title page.
Source of Description: This bibliographic record is available under the Creative Commons CC0 public domain dedication. The University of Florida Libraries, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.
Statement of Responsibility: by Byoung Kim.
Thesis: Thesis (Ph.D.)--University of Florida, 2009.
Local: Adviser: Roque, Reynaldo.

Record Information

Source Institution: UFRGP
Rights Management: Applicable rights reserved.
Classification: lcc - LD1780 2009
System ID: UFE0024858:00001


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DEVELOPMENT OF CONDITIONING AND TEST METHOD FOR ASSESSMENT OF DURABILITY OF FRC EXPOSED TO SEVERE ENVIRONMENTS By BYOUNGIL KIM A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY UNIVERSITY OF FLORIDA 2009 1

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2009 Byoungil Kim 2

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To my Wife and Son, Yookyung and Sunghoon, and my Father in Heaven 3

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ACKNOWLEDGMENTS I would first like to acknowledge my advisor, Dr. Reynaldo Roque, Professor in the Civil and Coastal Engineering Department for effectively supervising the project. His motivation and encouragement for me, along with his in-depth knowledge in research, were the driving factors for the success of this research effort. I would have not been able to reach this milestone if it was not for his advice and understanding. I would also like to express my gratitude to the other committee members, Dr. Mang Tia, Dr. Dennis R. Hiltunen, and Dr. Larry C. Muszynski, for their great enlightenment and keen research assistance. I would also like to thank Dr. Andrew Boyd and Dr. Namho Kim for their assistance during the initial stage of the research work. Graceful acknowledgement extends to Florida Department of Transportation (FDOT) for providing the financial support, testing equipment, materials that made this research possible. The Florida Department of Transportation personnel Messrs. Michael Bergin, Charles Ishee, Mario Paredes, Chris Ferraro, and Richard Delorenzo are appreciated for their help with the entire process for fabricating test samples and performing testing. I really appreciate the help and guidance I received from George Lopp, Chuck Broward, Jimmy E. Joiner, and Tanya Riedhammer throughout my research and laboratory work. I would also like to thank all Korean students in our department and member of Gainesville Korean Catholic Community for sharing a lot of time together. Last but not least, my eternal thanks go to my mother, fatherin-law, mother-in-law, and my brother and sister, for their love, encouragement and consistent advice throughout my academic life. 4

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TABLE OF CONTENTS page ACKNOWLEDGMENTS ...............................................................................................................4 LIST OF FIGURES .......................................................................................................................10 ABSTRACT ...................................................................................................................................15 CHAPTER 1 INTRODUCTION..................................................................................................................17 1.1 Background...................................................................................................................17 1.2 Objectives......................................................................................................................18 1.3 Scope.............................................................................................................................19 1.4 Hypothesis.....................................................................................................................19 1.5 Research Approach.......................................................................................................20 2 LITERATURE REVIEW.......................................................................................................22 2.1 Introduction...................................................................................................................22 2.2 Microstructure of Fiber-Matrix Interface......................................................................23 2.3 Mechanical Behavior of Fiber Reinforcement..............................................................25 2.3.1 Stress Transfer before Matrix Cracking............................................................26 2.3.2 Stress Transfer after Matrix Cracking...............................................................29 2.4 Fracture Mechanics Approach......................................................................................30 2.4.1 Crack Suppression by Fibers.............................................................................30 2.4.2 Crack Stabilization Subsequent to Matrix Crack..............................................32 2.4.3 Fiber-Matrix Debonding...................................................................................32 2.5 Fiber Effect on Mechanical Properties..........................................................................33 2.5.1 Compression......................................................................................................33 2.5.2 Tension..............................................................................................................36 2.5.3 Bending.............................................................................................................37 2.6 Transport Mechanisms..................................................................................................39 2.6.1 Permeation........................................................................................................40 2.6.2 Absorption.........................................................................................................41 2.6.3 Diffusion...........................................................................................................42 2.7 Parameters Affecting Transport Properties...................................................................43 3 MATERIALS AND EXPERIMENTAL PROGRAM...........................................................46 3.1 Characterization of Constituent Materials....................................................................46 3.1.1 Cement..............................................................................................................46 3.1.2 Coarse Aggregates............................................................................................46 3.1.3 Fine Aggregates................................................................................................47 3.1.4 Chemical Admixtures.......................................................................................47 5

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3.1.5 Fibers.................................................................................................................47 3.2 Mix Proportions............................................................................................................50 3.3 Mixing and Curing Procedures.....................................................................................51 3.3.1 Mixing Procedure..............................................................................................51 3.3.2 Curing Procedure..............................................................................................52 3.4 Specimen Preparation....................................................................................................53 3.5 Experimental Program..................................................................................................55 3.5.1 Fresh Properties.................................................................................................55 3.5.1.1 Slump test...........................................................................................56 3.5.1.2 Inverted slump cone time....................................................................56 3.5.1.3 Vebe time............................................................................................58 3.5.1.4 Air content..........................................................................................59 3.5.2 Transport Properties..........................................................................................59 3.5.2.1 Permeable pore space test...................................................................60 3.5.2.2 Surface resistivity test.........................................................................60 3.5.2.3 Permeability test.................................................................................62 3.5.2.4 Absorption test....................................................................................63 3.5.2.5 Bulk diffusion test...............................................................................65 3.5.3 Mechanical Properties.......................................................................................66 3.5.3.1 Compressive strength testing..............................................................67 3.5.3.2 Splitting tensile testing.......................................................................68 3.5.3.3 Pressure tension testing.......................................................................69 3.5.3.4 Residual strength testing.....................................................................72 3.5.3.5 Flexural performance testing..............................................................74 3.5.4 Steel Bar Corrosion...........................................................................................76 3.5.5 Ultra Pulse Velocity (UPV)..............................................................................78 3.5.6 Scanning Electron Microscopy (SEM).............................................................78 3.5.7 Carbonation.......................................................................................................79 4 ENVIRONMENTAL EXPOSURE........................................................................................80 4.1 Introduction...................................................................................................................80 4.2 Deterioration of a Concrete Structure in Seawater.......................................................80 4.3 Environmental Exposure...............................................................................................82 4.4 Deterioration Mechanism..............................................................................................90 5 FINDINGS AND ANALYSIS...............................................................................................92 5.1 Introduction...................................................................................................................92 5.2 Fresh Properties Test Results........................................................................................92 5.2.1 Slump Test Results............................................................................................92 5.2.2 Inverted Slump Cone Test Results....................................................................92 5.2.3 Vebe Test Results..............................................................................................94 5.2.4 Air Content Test Results...................................................................................94 5.2.5 Relationships between Workability Tests.........................................................96 5.3 Transport Property Test Results....................................................................................98 5.3.1 Permeable Pore Space Test Results..................................................................98 6

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5.3.2 Surface Resistivity Test Results......................................................................100 5.3.3 Permeability Test Results................................................................................102 5.3.4 Absorption Test Results..................................................................................104 5.3.5 Bulk Diffusion Test Results............................................................................109 5.4 Mechanical Property Test Results...............................................................................111 5.4.1 Compressive Strength Test Results.................................................................111 5.4.2 Splitting Tensile Strength Test Results...........................................................111 5.4.3 Pressure Tension Test Results.........................................................................111 5.5 Steel Bar Corrosion Test Results................................................................................113 5.6 Evaluation of Beams Exposed to Conditioning..........................................................115 5.6.1 Visual and Photographic Inspection................................................................115 5.6.2 Ultrasonic Pulse Velocity Inspection..............................................................118 5.6.3 Permeable Pore Space Change........................................................................120 5.6.4 Average Residual Strength (ARS) Test Results..............................................121 5.6.5 Flexural Performance Test Results.................................................................123 5.6.6 Carbonation.....................................................................................................124 5.6.7 Scanning Electron Microscopy.......................................................................127 5.6.7.1 Fibers subjected to salt and acidic solutions.....................................128 5.6.7.2 Degraded beam.................................................................................129 5.6.8 Distribution Problem for Cellulose Fibers......................................................143 5.7 Discussion of Conventional Beam Approach.............................................................144 5.8 Summary of Conventional Beam Testing...................................................................150 6 DEVELOPMENT OF CONDITIONING AND TEST METHOD......................................152 6.1 Introduction.................................................................................................................152 6.2 Determination of Conditioning and Specimen Thickness..........................................152 6.3 Proposed Test Method................................................................................................153 6.4 Evaluation of Fiber Resistance to Conditioning.........................................................156 6.4.1 Experimental Program....................................................................................156 6.4.2 Exposure Conditions.......................................................................................157 6.4.3 Testing Procedures..........................................................................................157 6.4.4 Evaluation of the Fracture Tests.....................................................................158 6.4.4.1 Visual examination of fractured specimens......................................159 6.4.4.2 Examination of strength test results..................................................159 6.4.4.3 Examination of repeated load test results.........................................165 6.4.4.4 Evaluation of failure mechanisms of fibers......................................168 6.5 Summary of Findings..................................................................................................173 7 FINDINGS, CONCLUSIONS, AND RECOMMENDATIONS.........................................175 7.1 Summary of Findings..................................................................................................175 7.2 Conclusions.................................................................................................................179 7.3 Recommendations.......................................................................................................179 APPENDIX 7

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A FRESH PROPERTY TEST RESULTS................................................................................180 B DENSITY, ABSORPTION, VOLUME OF VOIDS TEST RESUTLS...............................181 C SURFACE RESISTIVITY TEST RESULTS......................................................................183 D WATER PERMEABILITY TEST RESULTS.....................................................................186 E ABSORPTION TEST RESULTS........................................................................................187 F BULK DIFFUSION TEST RESULTS.................................................................................189 G MECHANICAL PROPERTIES TEST RESULTS..............................................................198 H STEEL CORROSION TEST RESULTS.............................................................................203 I DEGRADED BEAM TEST RESULTS...............................................................................207 J INDIRECT TENSILE TEST RESULTS..............................................................................243 LIST OF REFERENCES.............................................................................................................246 BIOGRAPHICAL SKETCH.......................................................................................................252 8

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LIST OF TABLES Table page 3-1 Chemical and mineralogical composition..........................................................................46 3-2 Aggregate gradation, coarse aggregates............................................................................47 3-3 Aggregate gradation, fine aggregates................................................................................47 3-4 Properties of fibers used.....................................................................................................49 3-5 Environmental resistance of fbers used.............................................................................50 3-6 Material and mix proportions for Classes II/V concrete....................................................51 3-7 Number of specimens tested for mechanical tests for Classes II/V concrete....................54 3-8 Number of specimens tested for transport property tests for Classes II/V concrete..........54 3-9 Number of specimens prepared for conditioning and testing for Classes II/V concrete...55 3-10 Surface resistivity-permeability.........................................................................................62 4-1 Composition of simulated seawater...................................................................................83 4-2 Beam specimens exposed to environmental exposure.......................................................84 4-3 Redesigned composition of simulated seawater................................................................87 5-1 Percent change in UPV test results for Class II concrete.................................................119 5-2 Averaged UPV test results for Class V concrete.............................................................119 5-3 Averaged permeable pore space before/after conditioning for Classes II/V concrete.....120 5-4 Averaged ARS (psi) test results.......................................................................................121 5-5 Averaged test results of flexural performance.................................................................123 6-1 Number of specimens tested for IDT for Class II concrete.............................................157 9

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LIST OF FIGURES Figure page 1-1 Schematic diagram for research approach.........................................................................21 2-1 Schematic description of a fiber deformation and stress fields in the matrix....................27 2-2 Distribution of interfacial shear stresses and fiber tensile stresses....................................28 2-3 Interfacial shear stress distribution immediately after cracking........................................30 2-4 Idealized representation of an advancing crack and the stress field..................................32 2.5 ASTM C 1018 techniques of fiber reinforced toughness characterization........................39 3-1 Fiber types..........................................................................................................................48 3-2 Fiber surfaces (x500).........................................................................................................49 3-3 Compulsive pan mixer.......................................................................................................52 3-4 Concrete blocks for fiber mixtures....................................................................................53 3-5 Steel mold..........................................................................................................................55 3-6 Inverted slump-cone time test setup..................................................................................57 3-7 Vebe time test setup...........................................................................................................58 3-8 Surface resistivity test set-up.............................................................................................61 3-9 Water permeability test specimens....................................................................................63 3-10 Absorption test set-up........................................................................................................65 3-11 Exposure tank and specimen condition for bulk diffusion................................................66 3-12 Test set-up for compressive strength.................................................................................67 3-13 Test set-up for splitting tensile test....................................................................................68 3-14 Stress state in hollow cylinder under internal or external uniform pressure......................70 3-15 Nitrogen gas tension test and stress state...........................................................................71 3-16 Pressure tension testing equipments..................................................................................71 10

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3-17 Test setup for measuring residual strength by using deflection gage and yoke.................72 3-18 Load vs. deflection curve for residual strength measurement...........................................73 3-19 Test set-up for measuring flexural performance of FRC with yoke..................................74 3-20 Examples of parameter calculations for different flexural curves.....................................75 3-21 Test set-up for steel bar corrosion......................................................................................77 4-1 Schematic diagram for degradation mechanism of a concrete structure...........................80 4-2 Flow chart for experimental program................................................................................84 4-3 Environmental exposure conditioning...............................................................................84 4-4 New wet/dry environmental exposure conditioning..........................................................87 4-5 Moisture movement with new wet/dry conditioning for limewater..................................88 4-6 Moisture movement with new wet/dry conditioning for saltwater wet/dry ......................88 4-7 Moisture movement with new wet/dry conditioning for limewater wet/dry.....................89 4-8 Moisture movement with new wet/dry conditioning for saltwater wet/dry.......................89 4-9 Expected deterioration mechanism....................................................................................91 5-1 Slump test results for Class II concrete..............................................................................93 5-2 Slump test results for Class V concrete.............................................................................93 5-3 Inverted slump cone time test results for Classes II/V concrete........................................94 5-4 Vebe time test results for Classes II/V concrete................................................................95 5-5 Air content test results for Class II concrete......................................................................95 5-6 Air content test results for Class V concrete......................................................................96 5-7 Inverted slump cone time vs. slump..................................................................................97 5-8 Vebe time vs. slump...........................................................................................................97 5-9 Inverted slump cone time vs. Vebe time............................................................................98 5-10 Permeable pore space for Class II concrete without/with fiber.........................................99 5-11 Permeable pore space for Class V concrete without/with fiber.........................................99 11

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5-12 Permeable pore space for Classes II/V concrete..............................................................100 5-13 Surface resistivity for Class II concrete...........................................................................101 5-14 Surface resistivity for Class V concrete...........................................................................101 5-15 Coefficient of permeability for Class II concrete with/without fiber..............................102 5-16 Coefficient of permeability for Class V concrete with/without fiber..............................103 5-17 Coefficient of permeability for Classes II/V concrete.....................................................103 5-18 Absorption vs. time for Classes II/V concrete.................................................................105 5-19 Absorption rate for Class II concrete with/without fiber.................................................106 5-20 Absorption rate for Class V concrete with/without fiber.................................................107 5-21 Absorption rate for Class II concrete...............................................................................108 5-22 Absorption rate for Class V concrete...............................................................................108 5-23 Chloride concentration for Classes II concrete................................................................109 5-24 Chloride concentration for Classes II/V concrete............................................................110 5-25 Coefficient of chloride diffusion for Classes II/V concrete.............................................110 5-26 Compressive strength for Classes II/V concrete..............................................................112 5-27 Splitting tensile strength for Classes II/V concrete..........................................................112 5-28 Pressure tension strength for Classes II/V concrete.........................................................113 5-29 Total times for initiation of steel corrosion for Class II concrete....................................114 5-30 Total corrosion rate for Class II concrete........................................................................115 5-31 Surface degradation comparisons for fiber type..............................................................116 5-32 Average residual strength results for Classes II concrete................................................122 5-33 Average residual strength results for Class V concrete...................................................122 5-34 Flexural performance comparisons for PP fiber mixes for Class II concrete..................124 5-35 Flexural performance comparisons for PP fiber mixes for Class V concrete..................125 5-36 Flexural performance comparisons for PVA fiber mixes for Class II concrete..............125 12

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5-37 Flexural performance comparisons for PVA fiber mixes for Class V concrete..............126 5-38 Flexural performance comparisons for Steel fiber mixes for Class II concrete..............126 5-39 Flexural performance comparisons for Steel fiber mixes for Class V concrete..............127 5-40 Degraded area and carbonated depth on fracture surface................................................127 5-41 Surface properties of PP fibers........................................................................................130 5-42 Surface properties of PVA fibers.....................................................................................131 5-43 Surface properties of cellulose fibers...............................................................................132 5-44 Surface properties of steel fibers......................................................................................133 5-45 PP fiber comparisons in limewater and saltwater immersion..........................................134 5-46 PVA fiber comparisons in limewater and saltwater immersion......................................137 5-47 Steel fiber comparisons in limewater and saltwater immersion......................................140 5-48 Cellulose fibers distribution.............................................................................................143 5-49 Test result for flexural beam testing with third-point loading.........................................145 5-50 PP fiber mix for limewater immersion for 27 months.....................................................146 5-51 PVA fiber mix for limewater immersion for 27 months..................................................146 5-52 Steel fiber mix for limewater immersion for 27 months..................................................147 5-53 Unstable failure in fiber-reinforced concrete...................................................................147 5-54 Coefficients for PP fiber beams.......................................................................................148 5-55 Coefficients for PVA fiber beams....................................................................................149 5-56 Coefficients for steel fiber beams....................................................................................149 5-57 Overestimated energy effect on determination of toughness...........................................150 6-1 Absorption depths vs. time for fiber type and Classes II/V concrete..............................153 6-2 Theoretical stress distribution and gage points spaced at depth/4...................................154 6-3 Superpave TM IDT specimen setup...................................................................................155 6-4 2-Dimensional FEM analysis for circle and square shapes IDT......................................155 13

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6-5 Proposed test Specimen and stress distribution...............................................................156 6-6 Flow chart for experimental program..............................................................................158 6-7 Test Setup for IDT...........................................................................................................158 6-8 Surface degradation and failure plane for saltwater cyclic W/D.....................................160 6-9 Fractured surface degradation for Steel fibers.................................................................161 6-10 Comparison of strength test results at first cracking for PP-II mixes..............................162 6-11 Comparison of strength test results at first cracking for PVA-II mixes..........................163 6-12 Comparison of strength test results at first cracking for steel-II mixes...........................164 6-13 Repeated loading test results for steel fiber mix for Class II concrete............................166 6-14 Averaged horizontal permanent deformation vs. number of cycles for steel fiber mix..167 6-15 Averaged horizontal permanent deformation vs. number of cycles for PP fiber mix.....167 6-16 Averaged horizontal permanent deformation vs. number of cycles for PVA fiber mix..168 6-17 Schematic diagram explaining calculation procedure for resilient deformation ratio.....169 6-18 Resilient deformation ratio vs. no. of cycles for fiber bridging zone (steel fibers).........171 6-19 Resilient deformation ratio vs. no. of cycles for fiber bridging zone (PP fibers)............171 6-20 Resilient deformation ratio vs. no of cycles for fiber bridging zone (PVA fibers).........172 6-21 Rate of stiffness reduction of resilient deformation ratio................................................172 14

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Abstract of Dissertation Presented to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy DEVELOPMENT OF CONDITIONING AND TEST METHOD FOR ASSESSMENT OF DURABILITY OF FRC EXPOSED TO SEVERE ENVIORNMENTS By Byoungil Kim August 2009 Chair: Reynaldo Roque Major: Civil Engineering An experimental program was performed to evaluate durability of FRC produced with four fiber types (polypropylene/PP, polyvinyl-alcohol/PVA, hooked-end steel/St, and cellulose/Cell). The effect of cellulose could not be evaluated because good fiber distribution was not achieved in laboratory mixing. Transport properties indicated that the addition of fibers to concrete improved the resistance of mass transport of deleterious materials; steel fibers were best. Fibers provided for post-cracking resistance; again, steel fibers were best. FRC beams produced with two concrete classes were subjected to simulated saltwater (immersed and wet/dry) and swamp (acid) environments for 27 months. Effect of fibers on durability could not be assessed reliably based on test results from either average residual strength (ASTM C1399) or flexural performance tests (ASTM C1609) because of non-uniform degradation and stress/strain distributions, as well as development of multiple cracks. Indirect tension testing (IDT) was identified as a more effective approach to achieve a uniformly-degraded cross-section and uniform stress/strain distribution. FRC specimens were subjected to an additional six months of saltwater conditioning, after which cracking and post-cracking behavior was assessed with IDT using testing and data interpretation procedures specifically designed to capture the effects of 15

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fibers. Test results indicated that PP fibers had the best resistance to saltwater environments (immersed and wet/dry), while PVA fibers had the worst, and resistance of steel fibers was somewhere between these two. However, steel fibers did not do well in fully immersed environments, but showed little or no degradation in wet/dry environments. The detrimental effect of acetic acid on aggregate and cement overwhelmed the degradation mechanism in swamp water, so the effect of fibers could not be distinguished for this environment. It was concluded that PP has the best durability for non-structural applications in saltwater environments. Steel may be suitable in non-submerged saltwater environments, particularly for structural applications, but should not be used if it will be in direct contact with reinforcing bars because it was found to accelerate corrosion of the bars. PVA should not be used in saltwater environments. Finally, it was concluded that transport properties alone are not necessarily good indicators of resistance to degradation. 16

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CHAPTER 1 INTRODUCTION 1.1 Background Historically, there has been extensive research performed regarding the durability of concrete exposed to the marine environment. However, some mechanisms involved in the deterioration of concrete materials are not fully understood, particularly as related to fiber-reinforced concrete (FRC). Plain concrete, characterized by low tensile, flexural and residual strength as well as strain tolerance, requires reinforcement for structural usage. Traditionally, continuous reinforcing steel has been used in concrete structures to resist tensile and shear stresses. On the other hand, fiber reinforcement in concrete is comparatively short, discontinuous and randomly distributed throughout the concrete matrix. Currently, design codes do not allow the complete substitution of steel reinforcement with fibers alone as they do not provide sufficient resistance to tensile stresses of structural magnitude (ACI 544.1R, 1996). Therefore, fibers can be most effectively used to resist crack propagation, since they are more uniformly distributed throughout the concrete matrix and more closely spaced than traditional reinforcement. Furthermore, the addition of fibers into a cement matrix enhances fracture toughness by exhibiting much greater post-cracking resistance than plain concrete (Beaudoin and Bentur et al., 1990). Regourd (1980) indicated that marine structures typically are slowly degraded by chemical and physical mechanisms. Deleterious materials are transported into the concrete through absorption, diffusion, and permeability processes. Deterioration may occur as a result of lime dissolution and formation of ettringite, which is an expansive reaction that may lead to cracking, spalling, and subsequent erosion. For the case of cyclic wetting and drying, both chemical and physical processes are involved in the fundamental mechanisms that attack the marine structure. 17

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Typically, wetting and drying cycles result in leaching of concrete and accelerated ingress of saltwater through repeated adsorption. Ingress of chloride ions results in corrosion of reinforcing steel, which causes expansion that leads to tensile stresses. In addition, mechanical wave action and rapid changes in temperature and wind conditions result in additional tensile stresses of a physical nature. Almost all durability research performed to date on fiber-reinforced concrete has not considered transport characteristics such as permeability, diffusion, absorption and wicking action which are the fundamental mechanisms involved in the deterioration process of concrete during environmental exposure. Therefore, utilizing concrete materials typically used in Florida, the current state-of-practice, and manufacturers recommended guidelines, this research is focused on development of a better understanding of the fiber and fiber type effect on transport mechanisms that affect durability and on finding effective test methods to observe and evaluate the chemical and physical changes in the fiber-cement interface. 1.2 Objectives Although this work originally focused on evaluating the degree of degradation from the measurement of strength and toughness loss with conventional beam specimens, serious problems were encountered in terms of accelerated degradation mechanisms using flexural beam specimen. Therefore, the research was necessarily refocused to investigate and develop alternate advanced evaluation procedures for durability of fiber-reinforced concrete. The focus was to identify a critical transport mechanism for affecting effective degradation conditioning of FRC specimens in the laboratory. A second goal was to identify and/or develop a proper test method that is sensitive to failure mechanism of fibers during post-cracking behavior. Detailed research objectives are as follows: To examine the effects of fiber and fiber type on fresh and hardened properties of concrete. 18

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To evaluate the effect of fiber and fiber type on transport mechanisms that affect concrete durability. To identify and develop accelerated degradation conditioning with an effective specimen preparation and testing systems to evaluate the effect of fiber type on the potential of concrete to fail in service. To visualize the various interfacial microstructure and morphology changes resulting from chemical attacks by using a scanning electron microscope (SEM). To propose recommendations and guidelines for the establishment of an environmental conditioning system and an effective test method for assessing effect of fibers on degradation of FRC for the use of structural and non-structural fibers in Florida. 1.3 Scope The evaluation performed in this investigation involved the following: Ten mixtures involving two concrete mixture types, four kinds of fiber (polypropylene, polyvinyl alcohol, cellulose, and steel) and an unreinforced concrete group were evaluated. Fiber contents and mixture designs were based on current state-of-practice and manufacturers recommended guidelines. Compressive strength, splitting tension, pressure tension, flexural beam and indirect tensile tests were performed to evaluate fiber and fiber type effects on mechanical properties. Permeable pore space (voids), water permeability, chloride diffusion, and absorption tests were performed to determine the fibers effect on transport mechanisms, as well as to establish conditioning and appropriate specimen geometry for effective accelerated deterioration of the FRC. Simulated environmental exposure involved three kinds of conditioning systems; 1) salt water immersion; 2) salt water wet/dry cycles; 3) swamp water immersion (acid environment). Results of flexural beam and indirect tensile test were compared to identify effective conditioning systems and test methods for evaluation of degraded fiber-reinforced concrete. SEM/EDS image analysis was performed to discern the nature of the deterioration mechanism. 1.4 Hypothesis The hypotheses of this research are: 19

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The addition of fibers, as well as fiber characteristics, can affect the transport mechanisms of deleterious solutions through concrete, which in turn influence the degradation of physical properties and the durability of FRC subjected to different environments. High salt solution, high temperature, pre-cracked beam, and repeated wetting and drying cycles can accelerate degradation mechanisms. 1.5 Research Approach A schematic diagram for the research approach used is presented in Figure 1-1. The evaluation of the effects of fiber on degradation of concrete was based on a detailed literature review and laboratory investigation. This research not only investigated conventional approaches using the flexural bending test method, but also proposed a new conditioning system and specimen geometry for accelerating deterioration mechanisms, as well as a test method and data interpretation procedure to effectively evaluate the relative durability of FRC subjected to aggressive environments encountered in Florida. 20

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Literature Review Fresh/Hardened Properties Transport Properties New Conditioning System Effective Acceleration Method/ Specimen Thickness Fresh & hardened properties Conditioning system Durability evaluation Workability Compression/tension tests Flexural beam Permeable pore space Water permeation Ionic diffusion Absorption Surface resistivity Steel bar corrosion Recommendation & Guidelines of Environmental Conditioning S y stem&Effective Test Metho d Continuous salt water Wet/Dry salt water Continuous swamp water Conditioning System Beam/IDT SEM/EDS Figure 1-1. Schematic diagram for research approach 21

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CHAPTER 2 LITERATURE REVIEW 2.1 Introduction A literature review was undertaken to develop a better understanding of the effect of fibers on mechanical and transport properties of concrete. The literature review was also used to identify potentially suitable environmental conditioning procedures and effective test methods to evaluate the effects of chemical and physical changes in the fiber-cement interface. Interfacial microstructure, mechanical behavior of fibers in composites, transport mechanisms, and fracture mechanics for quasi-brittle fracture were reviewed. Although concrete is generally a durable material, it is vulnerable when exposed to environments that can chemically and physically attack its integrity. Many types and sources of chemical and physical attacks can affect the integrity of concrete. Solutions in the mixing water or adsorbed water may lead to cracking, spalling, and subsequent erosion. Ingress of chloride ions results in corrosion of reinforcing steel, which causes expansion that leads to tensile stresses and potential cracking. Wetting and drying cycles result in leaching and accelerated ingress of solutions. Presence of expansive clays, organics, and salts can also have detrimental effects on durability. Wave action in tidal zones and rapid changes in temperature, wind, and moisture conditions result in mechanically induced tensile stresses that can contribute to cracking. Although one factor may cause the primary distress, other factors may then contribute and accelerate the circumstance (Mindess et al., 2003). The main motivation for conducting durability studies is to accurately predict material behavior based on short-term testing. By conducting a literature review, a fundamental understanding regarding the development of degradation conditioning systems and effective test 22

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methods for failure mechanism of fibers was created. The reliability and practicality of these approaches for use in fiber-reinforced concrete were examined. 2.2 Microstructure of Fiber-Matrix Interface It is well known that the aggregate particles in concrete mixture are surrounded by a uniform matrix of hardened cement paste producing an interfacial transition zone (ITZ), which is typically 20-40 m thick. The structure of ITZ is quite different than that of bulk paste away from the physical interface. The ITZ is characterized as having the following properties: less unhydrated cement, a higher porosity, less C-S-H, large oriented crystals of CH, and a greater concentration of ettringite. Although the ITZ is quite thin, the interfacial region normally makes up 20-40% of the total volume of cementitious matrix which affects transport and mechanical properties of concrete (Mindess et al., 2003 and Metha et al., 2005). The process of development of interfacial zone resulting from the addition of fibers into concrete is similar to that between hardened cement paste and coarse aggregate. The discontinuous fiber reinforcement usually results in modification of the microstructure of cementitious composites by reduction of the number and size of mesopores rather than by an increase in number and size of micropores (Beaudoin, 1990). The microstructure of the transition zone in the area of the fiber reinforcement is quite different from that of bulk matrix and is strongly dependent on fiber type, fiber geometry, and the production process. The bonding property of the fiber-matrix interface and the debonding process of the fibers from the matrix affect the failure mechanism of concrete. Stress concentrations may develop at the fiber-matrix interface, which may lower resistance to micro-damage compared with conventional concrete. Conversely, the fibers resistance to pull-out or debonding may help to redistribute stresses over a broader area, which may result in greater resistance to further development of micro-damage, crack initiation, and propagation compared with conventional concrete. The discrete cement 23

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particles vary from 1 to 10 m in the fresh mix condition reacting with water to form poorly crystallized calcium silicate hydrate (C-S-H), large crystals of calcium hydroxide (CH), and a small amount of ettringite (Mindess, 2003). The nature of cement particles around the discrete fibers results in the development of water-filled spaces during mixing because of water bleeding and entrapment, and inefficient packing of cement grains around the fiber surface (Bentur and Mindess, 1990). Therefore, the microstructure of the transition zone at the interface becomes porous, allowing the crystallization of hydration products. Al-Khalaf et al. (1979) and Pinchin et al. (1978) studied the microstructure of the interfacial transition zone (ITZ) with steel fibers. They found that the interfacial zone is somewhat porous and abundant in CH, mostly in direct contact with the fiber surface, which differentiates it from the microstructure of the bulk paste matrix. The nucleation of a CH rich zone around the fiber surface results from the CH precipitation at the water-filled spaces in the fresh mix. The CH layer as thin as 1 m is not necessarily uniform around the fiber and it consists of a duplex film, and needle-like materials (C-S-H, ettringite). On the other hand, synthetic fibers such as polypropylene fiber with a low modulus of elasticity and polyvinyl alcohol fiber with a high modulus have different microstructure in the transition zone. Rice et al., (1988) and Bentur et al., (1989) found that the interfacial microstructure of fibrillated polypropylene fiber was fairly dense and continuous around the fiber surface and did not contain CH zone at the ITZ because a proprietary surface treatment involving wetting agents and physical roughening of the fiber surface to achieve bonding with the hardened cement paste caused the uniform formation of this dense layer. Hikasa et al. (1986) reported that the interfacial microstructure between cement paste and polyvinyl alcohol with high modulus of elasticity provided a uniform, highly effective reinforcing bond without formation of CH at the 24

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fiber ITZ due to their consistent fiber dispersion in the composites and the high area of fiber surface beneficial for improvement of interfacial bonding. 2.3 Mechanical Behavior of Fiber Reinforcement Short fibers in cement composites are discontinuously dispersed in the matrix during mixing and produce anisotropy and heterogeneity. Krenchel (1975) and Romualdi et al. (1964) suggested that fiber spacing is a geometrical parameter which plays an important role in governing the fiber performance in the composite. The average fiber spacing has been calculated by assuming a uniform fiber distribution within the hardened cement paste matrix. The suggested equation for the spacing of a cylindrical fiber is represented as follows: fVdKS (2-1) where S = fiber spacing K = constant from 0.8 to 1.1d = fiber diameter 2 depending on the fiber orientation Vf = fm during fibers is to increase the fracture toughness by arresting cracks and delaying crack propahe iber volume fraction. Beaudoin (1990) stated that the applied load is transferred from the hardened cement paste matrix to the fiber by shear deformation at the paste / fiber interface. The mechanical properties and geometry of both the fiber and matrix significantly affect the load transfer mechanisthe fiber pull-out process from the hardened cement paste matrix. The role of short and discontinuous gation. Bentur and Mindess (1990) determined that the fibers effectiveness in improving the mechanical properties through fiber-cement paste interactions is governed by both the load transfer process from the matrix to the fiber and the bridging effect across the crack surface. Tstress transfer from the matrix to the embedded fiber prior to crack coalescence in concrete is 25

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elastic in nature. Stress due to loading developed between the matrix and fibers is a shear stress which distributes the applied load across the interface, and the strains developed at the concrete matrix ITZ and the fiber are of the same magnitude. After the initiation of cracking, debondiof the fibers from the hardened cement paste matrix is caused by frictional slip, which is an important mechanism during the post-cracking process. Stress transfer from elastic deformation to inelastic frictional slip at the interface happens when the interfacial shear stresses developed the early stages of loading surpass the shear bond strength or fiber-matrix shear strength at theinterface. Therefore, the load transition mechanism of the shear stress along the fiber-matrixinterface is primarily important in controlling and evaluating mechanical behavior of fiber reinforced concrete an ng at d also valuable to assess effect of fibers in the various environmental 2.3.1 atrix edded in fiber, and for interfacial shear stress, (x), as a function of the distance x from the end of fiber: exposure conditions. Stress Transfer before Matrix Cracking During early stages of loading, load is transferred from the hardened cement paste mto the fiber in an elastic fashion and is the dominant stress transfer mechanism. The first analytical model for the stress transition in the early stage of loading was developed by Cox (1952). This model is based on the stress analysis surrounding a discontinuous fiber embthe matrix. A schematic description showing deformation changes before and after load application is shown in Figure 2-1. Cox (1952) derived the equation below for tensile stress, f (x), in the 2 cosh)2(cosh1)(11lxlExmff (2.2) 26

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27 2 cosh)2(sinh)/ln(2)(112/1lxlrREGExfmmf (2.3) where 2 /1 21)/ln(rRrEm 2G f (2.4) r = radius of the fiber Ef = modulus of elasticity of the fiber The maximum interfacial shear stress is created ainterfacial sFigure 2-1. Schematic description of a fiber deformation and stress fields in the matrix. A) Before loading. B) After loading. C) Stresses. (after Bentur et al., 1990). R = radius of the matrix around the fiber l = length of fiber G m = shear modulus of the matrix at the interface. t the ends of fiber and gradually decreases and finally drops to zero toward the center of the fiber as depicted in Figure 2.1c. Note that hear stresses are greatest at the end of the fiber and decrease towards the A BShear Stress Tensile Stress R L P P C

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fibers center. Since the shear stresses act away from the center of the fiber, the maximum ten sile stress within the fiber occurs at the fibers center and goes to zero at the end of the fiber. If the fiber debonds at the interface before matrix cracking, the interfacial slip resistance mechanism between the fiber and the matrix should be considered for calculation of stress distribution (Bentur and Mindess, 1990). Figure 2.2 is an illustration of the distribution of shear stresses and tensile stresses. (after Bentur et al., 1990). e are ure 2-2a. However, when the interfacial shear stress reaches or exceeds the shear bond tributing gure 2P 0 P 1 P 2 P 3 P 0 P 1 P 2 P 3 aaaP 1 2 3 1 2 3au P P P 0 fu a 123PP aa1P 2 3P 0 y t A B Figure 2-2. Distribution of interfacial shear stressshear stresses. B) Fiber tensile stresses es and fiber tensile stresses. A) Interfacial Figure 2.2a illustrates the stress distribution of the interfacial shear stress. It is assumed that under a given load P 1 P 2 P 3 the frictional slip in the debonded region a 1 a 2 a 3 produces a uniform frictional shear stress distribution, fu at the interface as shown in Figure 2.2a and the tensile stress distribution as shown in Figure 2-2b. Before reaching the adhesional shear bond strength, au the shear stress distributions by the applied load (P 0 ) at the interfacas shown in Fig stress, au (at load P 1 ) debonding zone (a 1 ) is created from the end of fiber by disuniform interfacial shear stress ( fu in Figure 2-2a) and building up the tensile stress in Fi2b. The interfacial shear stress slowly decreases to zero beyond debonding zone (a 1 ). The length 28

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of debonded zone increases or changes as the applied load increases by following the prestress transfer mechanisms at the interface. 2.3.2 Stress Transfer after Matrix Cracking The major benefit of fiber reinforcement in composites is realized in the post-cracking process by arresting crack propagation from the fiber pull-out in the matrix rather tha vious n by controspect tion 2.3.1. The main difference for post-cracking behavior of fiber reincrete materials is that the maximum (Bentur et al., 1990). When external loading causes the elastic shear stress to exceed the adhes to the fiber at the debonded zone is frictionally slip based at the interface. Subsequent to debonding, the elastic shear stress is redistributed at the end of the debonded zone in the fiber, thus preventing catastrophic failure immediately after the matrix crack. tion and elastic shear stress distribution decreasing away from the cracked surface. e of debonding prior to matrix cracking, there is no frictional slip at the Figure 2-3 (b). When the post-cracking mechanism acial shear stress and ibutions between the fiber and the matrix. lling stress-strain curve prior to matrix cracking. Therefore, the fiber pull-out mechanism representing bridging resistance forces across a crack surface is an important aspect with reto the effect of fiber type with different mechanical and geometrical properties in the post-cracking zone. The shear stress transfer mechanisms during fiber pull-out from the matrix have fundamentally the same process as those examined in previous Sec forced con interfacial shear stress takes place at the fiber embedment point in the cracked composites ional shear bond strength, debonding occurs and then load transfer mechanism from the cement paste matrix Figure 2-3 (a) illustrates the combined mode with frictional shear stress distribution at the intersec However, in the absenc fiber-crack intersection as shown in prgresses with increased loading, it combines and represents both interf o elastic shear stress distr 29

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Figure 2-3. Interfacial shear stress distribution immediately after cracking. A) Debonding preceded cracking. B) No debonding prior to cracking. (after Bentur et al., 1990). An analytical model of fiber pull-out of a single fiber in the matrix has been proposed by Greszczuk (1969): )cosh()coth(sinh2)(2222xlxrx P (2.5) 2/1 2fimrE 2bG (2.6) bi = effective width of the interface l = embedded length. 2.4 Fracture Mechanics Approach Linear Elastic Fracture Mechanics (LEFM) first assumes that the material is isotropic and linear elastic. Based on the assumption, the stress field near the crack tip is calculated using the theory of elasticity. When the stresses near the crack tip exceed the material fracture toughness, the crack will grow. The Linear Elastic Fracture Mechanics (LEFM) approach may be an where r = radius of the fiber E f = modulus of elasticity of the fiber G m = shear modulus of the matrix at the interface au fu A xx au B 30

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appro -matrix debonding mechanism which 1990). tending further than the fiber due to the stress concentrations just in front of crack tip, but the fibers apply pinching forces through redistribution of interfacial bond stresses subsequent to matrix cracking and decrease the stress intensity factor of the crack. Higher stresses, then, are needed to produce a stress field in front of the crack tip so that the maximum stress surpasses the critical stress intensity factor of the matrix to further crack propagation. The spacing factor concept relating to the required stress to cause the matrix crack was e to first er, there are several limitations regarding the application of the sp priate model to predict the fiber pull-out effect in FRC, but it is limited to first cracking.The most critical effect of fiber reinforcement in cement composites is to enhance post-crackingbehavior. Three important aspects should be considered for the application of fracture mechanics to the fiber-crack interaction of FRC. First, crack suppression which is the increase in stress required for crack initiation due to the addition of fibers. Second, crack stabilization which refers the crack arresting onset of first matrix cracking. Third, fiber refers crack propagation along the interfacial transition zone (Bentur and Mindess,2.4.1 Crack Suppression by Fibers LEFM applications for the crack suppression, which is the increase of stress needed for crack initiation due to the addition of fibers in fiber cement composites, were studied by Romualdi et al, 1963. The extensions of both the fiber and the matrix prior to crack initiation are the same under tensile loading. However, subsequent to matrix cracking, the behavior between the fiber and matrix is different. The matrix has a tendency of ex used to demonstrate its validity for predicting the beneficial effect of fiber on resistanc crack (Romualdi et al., 1964). Howev acing factor concept to FRC. The spacing factor must account for fiber length, diameter effects, the fiber orientation, and the characteristics of the fiber-matrix bond, i.e., perfect bond. 31

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2.4.2 Crack Stabilization Subsequent to Matrix Crack Fibers tend to arrest cracks within the matrix at the crack surface. There are many analytical models that attempt to explain the complex cracking patterns at the crack tip. The stress transfer mechanism across the crack proposed by Wecharatana and Shah (1983) can be seen in Figure 2-4. They suggested that three distinct zones can be identified at the fracture location: traction free zone where load transfer no longer takes place, fiber bridging zone where stress transfer occurs by frictional slip of fibers, and matrix process zone where continuity and aggregate interlock allow for stress transfer by the matrix itself. Figure 2-4. Idealized representation of an advancing crack and the stress field. (after Wecharatana and Shah, 1983). 2.4.3 Fiber-Matrix Debonding As discussed in the previous section, the major role of fiber reinforcement is to increasefracture energy or the toughness required for the crack initiation and propagation. There are two processes that affect the value of fracture energy: 1) fiber debonding; and 2) pull-out mechanisms from the matrix that are related to energy dissipation throughout the fracture process. The interface debonding is defined as the work done in breaking the interfacial sbond between the fiber and the matrix, and pull-out work is characterized as the work the hear done in extracting the fiber embedded in the matrix after cracking. Fracture mechanics has been used for m max P fmax If I P aeff Crack Length (a) Fi ber Bridging Zone Aggregate Bridging Zone Traction Free Zone Matrix Process Zone Fiber Brid g in g Crack Closing Pressure P P 32

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the modeling of fiber cositexplain the debonding iable manner, and to experimentally obtain the values of the interfacial shearory as: mpos to obtain materials parameters that can e mechanism in a more rel bond strength (Bentur et al., 1990). The tensile stress required for catastrophic fiber debonding was calculated by Outwater and Murphy (1969) using the classical Griffith the 2/18dGEwhere dbf (2.7) Gdb =E = the fiber modulus (Gc) 3) reported that the average value of Gc for steel fiber e er, fiber reinforcement usually has a relatively small effect in compression compared to the energy required to debond a unit surface area of fiber fd = the fiber diameter. The above analysis only considers the energy balance of the fiber. Subsequent to the study performed by Outwater et al. (1969), Stang et al. (1986) expanded the solution explaining the compliance of the entire system, including fiber and matrix. Morrison et al. (1988) furtherenhanced the explanation of the debonding and pull-out behaviors of fibers in composites by determining fracture parameter (G c ), which is the average critical strain energy release ratefor fiber debonding at the interface. Swamy (198 was determined to be 2.5 N/m, which is lower than the critical energy release rate of unreinforced mortar determined to be 5.3-12.3 N/m. The crack through the path of least resistance propagates along the fiber/matrix interface rather than through the matrix. 2.5 Fiber Effect on Mechanical Properties 2.5.1 Compression ACI Committee 544 (1989) reported that the discontinuous distribution of fibers in thhardened concrete matrix changes the failure mode by making the concrete more ductile. Howev 33

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the efoth ed slightly on the ascending portion of the curve and considerable divergence was obser y absorption prior to matrix failure. Naaman et al. (1993ne fiber 0) fect on tensile or bending properties. The effect of fibers in improving the compressive strength in the matrix relies on the properties of concrete having coarse aggregates. Fanella and Naaman (1985) studied that stress-strain properties of steel fiber reinforced mortar in compression. In their study, three fiber volume contents (1, 2, and 3%) and three aspect ratios (47, 83, and 100) were evaluated in combination with three mortar matrices with smoand brass-coated steel fibers. The test results showed that the stress-strain curves for the FRC diverg ved on the descending portion. A higher content of fiber volume resulted in more ductile behavior of the material subsequent to cracking, which resulted in greater toughness. The compressive strength increased from 0 to 15%. Naaman et al. (1993) reported that the effect of hooked steel fibers of 1.2 in. (30 mm) length, 1% volume content and an aspect ratio of 60 slightly increased the compressive strength of concrete by 17% relative to the control mix. Furthermore the failure strain was considerably increased, which resulted in a much larger area under the stress-strain curve and thus indicating asignificant improvement in ductility and energ ) also reported a 30% increase in compressive strength relative to the control mix by increasing the percentage of fibers from 1% to 2% by volume with the same fibers and aspect ratio. Malhotra et al. (1994) studied the mechanical properties of polypropylene fiber reinforced concrete. In this study, two experimental groups of 1.55-in length fibrillated polypropylewith 4 kg/m 3 (0.44%) and 5 kg/m 3 (0.54%) volume contents were used. The introduction of the fibers to the concrete showed no significant effect on the compressive strength. Yao et al. (200also observed that there was no significant improvement in the compressive strength using 34

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smooth and straight polypropylene fiber when the fiber content was 0.5% and the length wmm. In 2003, Choi et al. reported the test results of compressive strength of polypropylene fibreinforced concrete (PFRC). A monofilament fiber 0.90 mm in di as 15 er ameter and 50 mm in length was ur rapid (1993) reported that polypropylene fiber mixes containing 1% or 2% by volumUnlike e % % polyvinyl alcohol fiber with 12 mm length decre sed. The fiber contents were 1.0% and 1.5% of the mixed concrete by volume. Polypropylene fibers with a wavelength shape and collated in small bundles were used fointroduction into concrete mixtures. PFRC samples broke with vertical cracks at about 70-85% of the peak load. The average compressive strength showed that the polypropylene fibers did not contribute to the improvement of the compressive strength, although the strains at the peak load increased significantly, as did the toughness. Naaman et al e with 0.75-in in length showed a significant reduction in the compressive strength. the steel fiber mix at 1% and 2% volume fraction, the polypropylene mix at 1% and 2% volumfraction showed a significantly lower ductility. They concluded that this lower ductility may be attributed to the low elastic modulus of the polypropylene fibers and their poor bonding properties in comparison with steel fibers. Leung et al. (2005) investigated the addition of 0.5polypropylene fiber with 15 mm length and 0.5 ased the compressive strength about 10% for PP and 15% for PVA fibers in comparison with plain concrete. They explained that the introduction of small diameter fibers into the mixture makes mix compaction more difficult, and hence, more entrapped air exists in the finalmixture. Also, 1% of polyvinyl alcohol fiber with 12 mm length did not alter the compressive strength significantly at 28 day (Schwartzentruber et al., 2004). 35

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Generally, the addition of steel fibers improves the bonding mechanism at the fiber-hardened cement pa ste matrix interface and might be helpful to obtain the high strength comprs tic r ion crete gth about 9% in comparison with te. Shaaban and Gesund (1993) carried out splitting tensile tests with 6 x 12 in spe ile mixes with 0.2% by volume of concrete has been reported to be 2-8% higher than that of ordinary concrete mixes ared with unreinforced concrete, though it strongly depends on fiber length, fiber geometry, fiber volume fraction and aspect ratio of fiber. On the other hand, the addition of synthetic fibeto concrete has not shown improvement in the compressive strength as results of their low elasmodulus and poor bonding properties at the hardened state. 2.5.2 Tension ACI committee 544 (1999) reported that the use of the splitting tensile strength test (ASTM C 496) for FRC specimens is not recommended for analysis of the behavior of fiber reinforced concrete subsequent to cracking due to unknown stress and strain distributions aftethe facture. Strain gauge or other sensitive methods of crack detection, such as acoustic emissor laser holography can be used for the identification of the first crack and analysis of stress-strain distribution for post-cracking behavior. Yao et al. (2003) investigated the mechanical properties of steel fiber-reinforced conwith 0.5% fiber volume fraction. The steel fibers were hooked end and 30 mm in length. The authors found that the addition of steel fibers increased stren unreinforced concre cimens containing 1 in corrugated steel fibers and fiber contents of 0, 79, 157, 235, and313 lb/yd 3 of concrete. Test results showed that steel fiber can significantly enhance the tensstrength of concrete. The load at first visual crack was used for the determination of the tensile strength of SFRC. Al-Tayyib et al. (1998) reported that little increase in strength has been observed regarding the addition of synthetic fibers to concrete. The tensile strength of PFRC 36

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with t as noticed ity econd st with the previo on t e. m load-controlled testing are different from those of ASTM C 1018 ach, which is easy to prepare and simulates practical loading conditions in FRC applications, is normally recommended for measuring toughness in FRC. However, there are some concerns with determination of toughness test procedures specified in ASTM C 1018, representing he addition of polypropylene fibers with 0.8 in fibrillated bundles. Choi et al. (2005) found that the average splitting tensile strength of PFRC increased by approximately 20-50% using 0.9mm diameter and 50 mm length PP monofilament fibers at volumes of 1% and 1.5%. Moreover,the addition of polypropylene fibers largely increased the ductility of the concrete. It wthat the stress-strain curve was linear up to the proportional limit after which stress capacsharply decreases, while the strain increased, and then increased again by showing a speak. This post behavior was repeated several times until the final failure. Yao et al. (2003) reported the mechanical properties of polypropylene fiber at 0.5% fiber volume fraction. The polypropylene fibers were smooth and straight with a 15 mm length. In contra usly cited work, they found that the addition of polypropylene fiber showed no effectsplitting tensile strength in comparison with plain concrete. 2.5.3 Bending The third point loading test specified in ASTM C 78 (2004), C 1018-97 (2004), and C 1609-06 (2008) is commonly used to measure flexural strength of FRC. Maximum flexural strength is determined at the first peak load as that value of load corresponding to the first poinon the load-deflection curve where the slope is zero, that is, the load is a local maximum valuTest procedures of ASTM C 78 fro or C1609, which are handled by deflection-controlled procedures. ACI Committee 544 (1999) reported that an important material property from FRC testing is toughness, which is the energy absorption capacity of a material and can be used to evaluate the effect of fibers or crack propagation. The conventional flexural test appro 37

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serviceability-based toughness indexes and the first-crack strength of FRC as shown in Figure 2-5. Toughness indexes are calculated in terms of energy ratios: the energy absorbed to a certain multiple of first crack deflection to the energy absorbed up to the first crack. Banthia and Trottier (1995) reported that measuring true specimen deflection at first cracking, which is very important to identify toughness indexes, is difficult due to seating or the downward movement of the specimen. Determination of first cracking point is another issue because the initial ascending part of the curve has considerable nonlinearity before reaching the peak load. Finally, FRC with low fiber volumes or with high-strength matrixes mostly generates instability subsequent to matrix cracking. The sudden high energy dissipation and high rate of deflections at first cracking significantly affect measurement of load-deflection curve during post-cracking behavior of fibers. ASTM C 1609-06 was recently accepted as a test method to replacement of ASTM C 1018-97. While the proposed new test method maintains the procedures for obtaining the flexural tion curve is completely different. Detailedter 3. load-deflection curve presently described in C 1018-97, the analysis of the load-deflec test procedures are described in Chap 38

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emical ions into concrete occurs via the pore system or mhemical or physical isms which control the media transport into the concrete, but the transport mechanism distribution or structure, concrete pore saturation, and temperature (Kropp et al., ultaneously operate to convey the transport rive the transport coefficient for specific conditions, investigations are normally limited to a single transport property. Transport Figure 2-5. ASTM C 1018 techniques of fiber reinforced toughness characterization 2.6 Transport Mechanisms The transport of water, gases and ch icro-cracks in the hardened cement paste. There are many kinds of c mechan strongly relies on various enviro nmental conditions, pore size characteristics of the solution, degree of 1995). Therefore, the transport mechanisms may sim of media into concrete. In order to d e experimental A I H G L K J B D 5.53 L/150 15.5 10.5O CE F L L/3 Net D e fl ect i o n H b /Area OAG I10 = Area OACI/Area OAG OAG I30 = Area OAEK/Area OAG ction at first-crack Load Toughness Indexes I 5 = Area OABH I 20 = Area OADJ/Area = Defle Residual Strength Factors R5,10 = 20 (I10-I5) R 10,20 = 10 (I 20 -I 10 ) 39

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properties for the use o f in theoretical models used for the evaluation of deleterious material transpe flow ort into concrete are presented in the following sections. 2.6.1 Permeation Permeation is the flow of a fluid under the action of a pressure head. For steady-statof a liquid through a saturated porous media material, the flow rate is described by Darcys law: ptA QlK w (2.7 ) where 232a porous medium under a unit pressure gradient and standard temperature conditions. The coefficient of permeability for a gas can be described by the following equation (Zagar, 1955): K w = coefficient of permeability (m) = viscosity of the gas (Ns/m 2 ) Q = volume of gas flowing (m) l = thickness of penetrated section (m) A = penetrated area (m) p = pressure difference (N/m 2 ) t = time (s). The permeation of a gas is defined as the rate of discharge of a gas under laminar flow conditions through a unit cross-sectional area of ))((2 2121 ppppptAQl (2.8) Kg = coefficient of perm2 = vi322t = time (s). Kg where eability (m) scosity of the gas (Ns/m 2 ) Q = volume of gas flowing (m) l = thickness of penetrated section (m) A = penetrated area (m) P= pressure at which volume Q is measured (N/m 2 ) P 1 = pressure at entry of gas (N/m) P 2 = pressure at exit of gas (N/m 2 ) 40

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2.6.2 Absorption Absorption is the material property which characterizes the rate of liquid penetr ation terial due to capillary action. The standard reference is to a tube in plants but can bide the l is what causes porous materials such as sponges to soak up liquids. n up by trt ism depends on the material surface tension, density and viscosity of the liquid, pore ity and continuity of capillaries) and on the angle of contact pore walls (Kropp et al., 1995). The liquid flow for steady-state capillary action is represented by Darcys law adjusted for non-saturated liquid flow as follows equation: through a porous ma e seen readily with porous paper. It occurs when the adhesive intermolecular forces between the liquid and a substance are stronger than the cohesive intermolecular forces insliquid. The effect causes a concave meniscus to form where the substance is touching a verticasurface. The same effect In concrete pore system, the liquid containing various deleterious materials is take his capillary action affecting the pressure in the complicated pore system. This transpo mechan structure (such as radius, tortuos between the liquid and the dxwp (2.9where dp/dx = gradient o dpkF) wf pore water pressure pw (N/m2) = viscosity of water (Ns/m2) kp = coefficieCapillary action mechanism in concrete subjected to seawater is very important with regard to the chloride movement process. First, un-saturated concrete in contact with seawater y capillary action, which is several orders of magnitude faster than the n of chloride ions by diffusion alone, thereby accelerating the initial progression of nt of water permeability (kg/m). absorbs the salt solution b penetratio 41

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chlorision to oe with uniform ture, diffusion processes tend to lead towards even distributions of molecules or ions (Bertolini et al., 2004). Ficks first law expresses the diffusion phenomenon under stationary conditions: de ions into the concrete. Chlorides then diffused into the tortuous pore system by diffumechanism and the penetration depth increases at a slower rate (Kropp et al., 1995). 2.6.3 Diffusion Diffusion is the movement of molecules or ions from a region of higher concentration ne of lower concentration by random molecules or ions motion. In a phas tempera dx dCDF (2.10) where F = m2D = d3 ass flux (kg/ms) iffusion coefficient (m 2 /s) C = concentration (g/m) x = distance (m). Diffusion coefficient depends on the type of diffusing ion, concrete properties and environmental conditions, which can change as a function of position and time. When diffusion process reaches stationary conditions, the mass flux relies on time and is controlled by Ficks second law predicting how diffusion causes the concentration field to change with time: 22xCtCwhere D = diffusion coefficient (m D (2.11) 2 /s) C = concentration (g/m3) x = distance (m) t = time. 42

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This equation is normally integrated by assuming that the surface concentration of the diffusing ions is constant with time and is identical to C s (C=C s for x=0 and for any t) with constant D through the concrete thickness, and that diffusion coefficient, D, does not initially include chloride ion (C = 0 for x>0 and t = 0). The solutio n of equation (2.10) is given by: DtxerfCts21) (2.12) where: xC,( ztdtezerf22)( ( 0is the error function. The obtained experimental data of C vs. x can be used to determine the diffusion coefficient (D) from the equation (2.11) using the least squares method. 2.7 Parameters Affecting Transport Properties rate into conc 2.13) Tyler et al. (1961) determined that water permeability governs the pressurized water flow rete, which can induce concrete failure when saturated concrete is frozen. Furthermore, permeability controls the flow rate of chemical solutions, which often contain durability of concrete structures. Neville (1971, 1981) studied that the water flow into concrete concrete and the heterogeneous nature of its components make the quantification of the compacted cement paste. The pore structure in the cement paste divide into gel pores occupying about 28% of the paste volume and capillary pores occupying between 0% and 40%, depending chloride and sulfate ions that drop the pH of concrete and accelerate steel corrosion rate in concrete structures. Therefore, the permeability of concrete significantly influences long-term can be fundamentally described as flow in a porous system. However, the porous nature of permeability process difficult. Permeability of the hardened cement paste has the greatest influence on permeability of concrete, because coarse aggregates are fully enclosed by the 43

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on the ratio of water to cementitous material (w/c) and the degree of hydration. Neville (1981) also reported that concrete with lower w/c ratio produce a lower volume of the capillary voids compared with concrete with higher w/c. Water-cement ratio is one of the important factors influencing permeability of concrete Powers et al. (1954) concluded that the higher the water-ceme fiber specimens may be the fiber effect on reducing internal microcracking (e.g., due to shrinkage) in the concrete so that the presence of fibers in the concrete increases the resistance to water penetration. The most important factor influencing water absorption rate is the connectivity of capillary pores, which is considerably affected by w/c ratio, aggregate, curing conditioning, age, and compaction. Schonln and Hisdorf (1989) tested the absorption of water by measuring the weight change with time. They concluded that the absorption rate is reduced as the water/cement ratio is reduced. Dhir et al. (1987) also found that the absorption rate is significantly reduced with low water/cement ratio. Additionally, Dhir et al. concluded that the absorption rate of concrete is reduced as the concrete is cured for longer duration time in a saturated condition. The curing conditions of test specimens also influence the absorption rate. Haque (1990) compared the rate nt ratio, the higher the coefficient of permeability. The aggregate in concrete also was a significant influence on concrete permeability. Neville (1981) stated that the aggregate decreases the effective area over which water can flow if it has very low permeability. In addition, the effect of aggregate on permeability is considerable because the travel path for solutions increases significantly around the aggregate particles. Leung et al. (2005) investigated the water permeability of concrete with steel, PP, and PVA fibers at V f = 0.5%. The results showed high variability on the coefficient of permeabilityamong three tested specimens. They concluded that the lower permeability for some 44

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of water absorption of water cured specimens. The absorption rate was reduced about 40% less for moist cured condition. The compaction effect on absorption has been studied by Hall (1989). Absorption rate is reduced when tamping time is increased for the same concrete composition, as well as longer concrete age, which reduces capillary porosity with the development of hydration reaction. Martys and Ferraris (1997) examined the effect of boundary conditions on water absorr sed in ginning of the test. Test results after the initial increase was observed in r due to the evaporation of moisture from the sides of specimens. On the and, the specimens placed in container without sealed sides showed the greatest rate of ary action due to little and no evaporation of moisture from specimen surfac ens to air stored specim ption. Test specimens were either stored in air without sealing the sides of specimens oplaced in container without sealing the sides of specimens. Specimens placed in air decreaweight for a specified time and were partially saturated at the be showed a rapid decrease in the rate of capillary action specimens exposed to ai other h capill e. 45

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CHAPTER 3 MATERIALS AND EXPERIMENTAL PROGRAM This chapter is divided into four sections: characterization of constituent materials; mix ixing and curing procedures; and fresh properties of unreinforced and fiber-rced concretCharacterization of Cement ASHTO cee II was used to achia lower heat of hydration and to resist ater and swamp water, etc.). The compounds contained were obtain proportions; m reinfo e. 3.1 Constituent Materials 3.1.1 A ment typ eve aggressive media (i.e., sea w ed from the manufacture and described in Table 3-1. Table 3-1. Chemical and mineralogical composition Chemical Composition Value (%) SiO 2 20.47 Al2O3 5.19 4.49 CaO 63.49 1.10 SO 5 alogical Composition Value (%) Fe 2 O 3 MgO 3 2.55 NaO 2 0.0 K 2 O 0.28 Miner C 3 S 54.38 C 2 S 17.98 6.16 13.66 C 3 A C 4 AF 3.1.2 Coarse Aggregates The coarse aggregate used in this research was crushed limestone with a maximum size of 0.375 in (9.5 mm). The reason for selecting a relatively small-size aggregate was to improve both the uniform distribution of fibers and the effectiveness of fiber reinforcement. The bulk specific gravity of the coarse aggregate was 2.28, the bulk specific gravity at SSD was 2.40, and the apparent specific gravity was 2.59. The absorption of the coarse aggregate was 5.18%. Gradation 46

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results for the coarse aggregates, as obtained from tests performed at the FDOT laboratories according to FM1-T027, are given in Table 3-2. Table 3-2. Aggregate gradation, coarse aggregates Sieve Size Weig Actual ht Retained (g) Cumulative Percentage Retained (%) Cumulative Percentage Passing (%) 1/2 in. 0.00 0 100 3/8 in. No.4 31.00 2 98 730.20 53 47 No.8 1231.60 90 10 No.16 1314.20 96 4 No.50 1330.20 97 3 3.1.3 Fine Aggregates The fineness modulus for the fine aggregate was 2.39. Following are the specific gravity values: 2.648 BSGOD, 2.650 BSGSSD, and 2.658 ASG. The Absorption of the fine aggregate was 0.18%. Gradation results for the sand, as obtained from tests undertaken in the FDOT laboratories according to FM1-T027, are given in Table 3-3. Table 3-3. Aggregate gradation, fine aggregates Sieve Size Actual Weight Retained (g) Cumulative Percentage Retained (%) Cumulative Percentage Passing (%) No.4 1.10 0 100 No.8 9.80 3 97 No.16 58.70 15 85 No.30 165.80 44 56 No.50 300.50 79 21 No.100 369.50 98 2 3.1.4 Chemical Admixtures Two water reducing admixtures were used in this study to increase the slump without adversely influencing air entrainment or setting times. The first was WRDA 60 by Wr. Grace Construction Products, which produces typically 8-10% water reduction set retardation. The 100lbs). The second and amount addition of WRDA 60 added was 195 to 390 ml/100kg (3 to 6 fl oz/ 47

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water reducer was WR ADVA 140 superplasticizer by WR Grace Construction Product, which is a high range water-reducing admixture. Addition rates of ADVA 140 superplasticizer can vary with type of application, but will normally range from 390 to 1300 ml/l00kg (6 to 20 fl oz/100 lbs) of cement. 3.1.5 Fibers Polypropylene (PP), polyvinyl alcohol (PVA), cellulose and steel fibers were used in this study. Photographs and properties of these fibers are presented in Figures 3-1 and Table 3-4. Surface properties magnified 500 times and environmental resistance of fiber type are also presented in Figure 3-2 and Table 3-5. The fibers were selected from four different manufactures i.e., Bekaert, Durafiber, Grace, and Kuraray. A B C D Figure 3-1. Fiber types. A) PP. B) PVA. C) Cellulose. D) Hooked-end steel. 48

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A B C D Figure 3-2. Fiber surfaces (x500). A) PP. B) PVA. C) Cellulose. D) Hooked-end steel Table 3-4. Properties of fibers used Manufacture BEKAERT GRACE DURAFIBER KURARAY Product Dramix Name ZP 305 STRUX 90/40 Buckeye UltraFiber 500TM RF 4000x30 Fiber Steel Polyethylene Virgin Cellulose Hooked-filament Length (in) 1.2 1.55 0.0826 1.19 Aspect Ratio(L/D) 55 90 117 45 Tensile Specific Gravity 7.85 0.92 1.1 1.3 Fracture Material Polypropylene/ Blend Polyvinyl Alcohol Fiber Type collated Monofilament 5mm x 6mm Chip MonoDiameter (in) 0.022 0.017 7.08x10-4 0.026 Modulus(GPa) 200 9.5 29 Strength(MPa) 1104 620 800 Absorption None None High Low Strain (%) 3-4 8 6-12 49

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Table 3-5. Environmental resistance of fibers used Fiber Type PP losSteel PVA Cellu e Surfac e Texture ootd sm h groove rough rough Absorption no ne esistance id, low high none Environmental R ac al kali, salt alkali alkali poor 3.2 Mixortionsc fiber mix dosabove 4 lb. (2.4 kgASHTO-AGC-ARTBf coarse aggregate and an increase of the mortar fraction to accommodate the increased surface area due to the synthetic fiber addition. The synthetic fiber mix dosages used in this study were 7.75 lbs/yd3. for polypropylene, 16.43 lbs/yd33e 333004). A series of ten concrete mixes were prepared with and without fibers. As m3333for FRC. Prop For syntheti ges a s/yd 3 /m 3 ) A A Joint Committee (2001) recommends a reduction o for polyvinyl alcohol, and 1.5 lbs/yd. for cellulose. Thus, the volume of the coarse aggregate was reduced by adjusting for each of the above synthetic fiber volumes. Also, somadjustment to the mix design is recommended for steel fiber-reinforced concrete (SFRC) fromdosage range of at and above 65 lbs/yd. (39 kg/m) in the mixture. The steel fiber mix dosages in this study were 120 lbs/yd. Therefore, the volume of the coarse aggregate was reduced to adjust for the steel fiber volume. The mix proportions used in this study were applicable to concrete of moderate and high compressive strength of 31 MPa for concrete Class II, designed for bridge deck and 45 MPa for concrete Class V, designed for special case at 28 days specified in the FDOT standard specification for road and bridge construction (2 entioned earlier, the fiber volume fractions for this study were: 7.75 lbs/yd. for polypropylene fibers, 16.43 lbs/yd. for polyvinyl alcohol fibers, 1.50 lbs/yd. for cellulose fibers, and 120 lbs/yd. for steel fibers corresponding to fiber contents of 0.5%, 0.75%, 0.1%, and 1% by total volume respectively. Table 3-6 summarizes the mix designs 50

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Table 3-6. Material and mix proportions for Classes II/V concrete Mix Types PC PP PVA Cellulose Steel W/C 0.44/0.370.44/0.370.44/0.370.44/0.37 0.44/0.37 Cement (lbs/yd3) 611/752611/752611/752611/752 611/752Water(lbs/yd3) 269/278269/278269/278269/278 269/278CA (lbs/yd3) 1444/14301424/14101414/14001439/1425 1407/139FA (lbs/yd3) 1490/13621490/13621490/13621490/1362 1490/136Fiber Content(lbs/yd3) None7.7516.431.5 120Air Target (%) 3333 Set Retarder(oz) 33.833.833.833.8 3High Range WR(oz) 120.3120.3120.3120.3 12 3233.80.3 Note: CA= coarse aggregate, FA= fine agg regate. 3.3 Mixing and Curing Procedures a high shcar pan mixer (Figure 3-3) with a maximum capacity of 27 ft3l ks prepared in 23 x 13 x 8 in wooden molds to ensure proper distribution of the fibers within tm blocks after 14 days of moist curgravel and sand were mixed for approximately 1 inutallow for water absorption. Next, the cem 3.3.1 Mixing Procedure Each batch was mixed in at the Florida Department of Transportation (FDOT) State Materials Office (SMO) concrete mixing laboratory. The limestone aggregate was batched at a saturated surface-wet condition. Saturation was achieved by soaking the aggregate in water for 7 days. Cylindrical specimens were prepared for compression, splitting tension, permeability, absorption, and volume of voids testing. Standard 4 x 8 in cylinder molds used to prepare specimen of contromixes. However, fiber-reinforced concrete specimens were prepared by coring 4 x 8 in cylindrical specimens from bloc he concrete. Cylinders were cored fro ing. The following mixing procedure was used for all mixes specified in ASTM C 192 except for the procedure of addition of fibers. First, me. Then 50% of the mixing water was added and the mixture was mixed for 1 minute to ent was added along with the remaining water 51

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containing the set retarder and high-range water reducing admixture. Mixing continued for er 2 minut anothes. All component materials except for fibers were added to ensure proper and unifo mix was placed into the appropriate molds, which were then placed on a vibrating table. The vibrating process was continued for approximately 1-2 minutes. rm mixing. Finally, fibers were added to the mix. Altogether, the additional mixing time took approximately 3-4 minutes to ensure a uniform fiber distribution and to minimize fiber segregation and balling effects. After completion of the batch, the Figure 3-3. High shcar pan mixer 3.3.2 Curing Procedure Curing of all specimens was carried out in accordance with ASTM C 192/C M-02 (2004) except for block specimens: after placement, these specimens covered with a plastic sheet and kept in their plastic or wood molds for 24 hours. The specimens were then removed from their molds and moved to the moisture curing room, which was maintained at 100% relative humidity and 72 F (23 C) until the time of testing. Blocks designated for coring were moved to UF concrete laboratory at 14 days of moist curing and cored. Continuous curing in fresh water was contained for another 2 weeks. 52

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3.4 Specimen Preparation Experimental tests for both mechanical and transport properties were conducted for two types of concrete specified in the FDOT standard specification for road and bridge constructio(2004): Class II concrete, designed for bridge deck, consisting of 0.44 w/c ratio fiber mixtures for PVA, 0.1% for Cellulose, and 1% for Steel). Class V concrete, designed for special case requ n containing four types of fibers with different fiber volume fractions (0.5% for PP, 0.75% iring high strength, consisting of 0.37 w/c ratio fiber mixtures with the same fiber volume fractions and fiber types as the Concrete Standard 4x8 cylindrical specimens were foritioo 8 14 23 in. blocks were prepared for fiber mixtures to ensure uniform dit the blocks as shown in Figure 3Class II. used for mechanical tests control mixtures. Add nally, tw fiber stribution throughou 4. Figure 3-4. Concrete bloc ks for fiber mThe blocks were cored to make 4 8 in. cylinders after 14 days of curing. Three control cylinders were cast before adding fibers to the mix for compression and splitting tension tests to obtain strength properties of the concrete without fibers, as well as absorption, permeability, and volume of voids tests. The cylinder was sliced and prepared for transport property test. Absorption test specimens were prepared by cutting the top 2 in. of the cylinder. Volume of est ixtures voids test specimens were prepared by cutting the middle 3 in. of the cylinder. Permeability t 53

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specimens were chosen from bottom 2 in. The number and size of specimens performed for each test is sued in Table-8. Beens for Plain concrete mixes werst by using dual steel beaold ever, for mixes 15 slabs (4 20 14 in.) were prepared to ensure rm fiber distribution, as shown in Figure 3-5. The slabs were sliced to make 4 44 in. individual beams after curing. Then, pre-crack bixture were produced using the third-point loading s were prepared to induce the field and accelerate damage mechanism during environmental expos any postmmari z s 3-7 and 3 am specim e ca indivi m m with 4 4 14 in. How fiber unifo 1 eams for each fiber m apparatus specified in ASTM C 1399 with a steel plate controlling the rate of deflection at the bottom of the specimen. Pre-cracked beam typical cracking of concrete in ure. However, cellulose fiber mixes were not prepared because they did not showcracking behavior subsequent to first cracking. The number of specimens prepared for conditioning and testing is summarized in Table 3-9. Table 3-7. Number of specimens tested for mechanical tests for Classes II/V concrete Com./ Splitting Tension Pressure Tension Mix Fiber f Type Type Fiber Volume Fraction V(%) Control/Fiber Control/Fiber PC Control N/A 3/0 3/0 PP Polypropylene Cell Cellulose 0.50 3/3 0/3 PVA Polyvinyl Alcohol 0.75 3/3 0/3 0.10 3/3 0/3 Steel Hooked Steel 1.00 3/3 0/3 Table 3-8. Number of specimens tested for transport property tests for Classes II/V concrete Absor./Permea./Voids Bulk Diffusion Mix TFiber Fiber Fraction Vf (%) ype Type Volume Control/Fiber Control/Fiber PC Control N/A 3/0 3/0 PP Polypropylene 0.50 3/3 0/3 PVA Polyvinyl lcohol 0.75 3/3 0/3 Cell Cellulose 0.10 3/3 0/3 Steel A Hooked Steel 1.00 3/3 0/3 54

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Figure 3-5. Steel mTable 3-9. Number of specimens prepared for conditioning and testing for Classes II/V concrete old: individual beam for control mixes (left); slab for fiber mixes (right) ASTM C 1399 ASTM C1609 Mix TFiber ype Type Fiber Volume Fraction V f (%) Uncracked Beam Precracked Beam Uncracked Beam P C Control N/A 25 N/A 25 PPCS P Polypropylene 0.50 25 25 25 VA Polyvinyl Alcohol 0.75 25 25 25 ell Cellulose 0.10 25 N/A 25 teel Hooked Steel 1.00 25 25 25 3.5 Experimental Program An experimental program was carried out to obtain a better understanding of the fiber afiber type on fresh, mechanical, and transport properties of FRC. 3.5.1 Fresh Properties The measurement of workability of FRC requires a different approach than with nd on in conventional concrete mixture, because the slump loss does not necessarily represent a corresponding loss of workability. One disadvantage of using fibers in concrete is a reductiworkability representing an increase of the stiffening effect in the mixture. The Vebe time and inverted slump cone time, which are plastic property tests that measure the energy required to compact the concrete, have been developed specifically to evaluate the fresh properties of FRC. The workability of FRC is affected by fiber aspect ratio and fiber volume fraction. As the fiber 55

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content or aspect ratio increases, the slump decreases. The fresh properties of FRC mixtures were evaluated with slump testing (ASTM C 143/C 143M-00), air content (ASTM C 231-97), inveslump cone time (ASTM C 995-94), Vebe time (ASTM C 1170-91) and unit weight (AST231-97). 3.5.1.1 Slump test rted M C ASTM C 143 for the slump test is a common, convenient, and inexpensive test, but it may owever, the slump test was performed with and the mixing procedure to compare the fibers effect on workability. A sample of fre d displaced position of the center of the top surface of the concrete is measured and reported as the slump of the concrete. 3.5.1.2 Inverted slump cone time ASTM C 995-94 is the standardized test method for inverted slump cone time and has been developed specifically to measure the workability of FRC. It effectively measures the mobility or fluidity of the concrete to flow through a confined space subjected to internal vibration. The test is not suitable for flowable mixtures of FRC, designed to flow freely through a confined space because the concrete tends to run through the cone without vibration. The inverted slump cone test method provides a measure of the consistency and workability of fiber-reinforced concrete. Figure 3-6 is photograph of the inverted slump-cone time test setup. The procedure was carried out according to ASTM C 995-94 as follows: the bucket was dampened and was placed on a level, rigid, horizontal surface free of vibration and other disturbances. e cone was dampened and was placed in the positioning device, where it was level. From the sample obtained, the cone was filled in three layers, each approximately one third of the volume of the cone. Each layer not be a good indicator of workability for FRC. H without fiber during shly mixed concrete was placed and compacted by rodding in a mold shaped as the frustumof a cone. The mold was raised, and the concrete allowed to subside. The vertical distance between the original an Th 56

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was li e ial that f the ghtly leveled with a scoop or trowel to minimize the entrapment of large voids and the surface of the top layer was stroked off by means of a screeding and rolling motion of the tamping rod. Protruding fibers that inhibited screeding were removed by hand. Then, an externalvibrator and a stopwatch were started simultaneously. The stopwatch was stopped when the conbecame empty, which occurred when an opening became visible at the bottom of the cone. Whenthe cone became plugged during the test, or failed to empty because of an excess of materhas fallen through during filling, the result was disregarded and a new test was performed on another portion of the sample. The time needed for the mix to flow out of the cone was recordedAs shown in Figure 3-6 an external vibration source was utilized for the consolidation oconcrete. The use of an external vibration is a slight deviation from ASTM C 995, which prescribes an internal source. However, the external vibration source was used because it provides more repeatability. Figure 3-6. Inverted slump-cone time test setup 57

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3.5.1.3 Vebe time ASTM C 1170 is the standardized test method for the Vebe time, which is intended to be used for determining the consistency and density of stiff to relatively dry concrete mix tures as show n in Figure 3-7. test setup The procedure for operating the Vebe time test is as follows. The Vebeconsistometer was installed on an unbending, horizontal and smooth surface, and the cylinder mold was put on the vibrating table and secured using the special screws. The conical mold was moistened, then put into the cylinder mold, and the funnel was positioned over the cylinder mold. The screw of the rotating arm was tightened so that the funnel prevented the mold from lifting. After the concrete was prepared, the conical mold was filled in three steps with 25 strokes of a tamping rod distributed uniformly over the whole surface. The conical mold was lifted vertically, avoiding sideways or torsional movements. The rotating arm was moved so that the transparent disk was Figure 3-7. Vebe time 58

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above the concrete surface, and the disk was lowered until it touched the concrete. The transparent disk was left free and the fixing screw on the holding bar w as unscrewed so that it movehen, the performed to confirm that the addition of fibers did not result in the entrapment of unwanted air voids within the concrete which may be as large as 3 nm and are capable of adversely influencing strength and impermeability (Mehta et al, 2005). Both effects would lead to decreases in durability performance. 3.5.2 Transport Properties Degradation of concrete structure is normally due to the movement of aggressive chemical ions (chlorides, sulfates, CO2) into concrete. Transport of water, chemical ions or gases into concrete occur through several kinds of transporechanisms such as diffusion, permeability by n by electr d freely inside the cylinder and touched the concrete, which was then compacted. Tvibrating table was operated and the timer was pressed. As soon as the transparent surface was completely covered by the fresh concrete, the timer and the vibrating table were stopped. Thisresulting time is the Vebe time and represents the workability of concrete. 3.5.1.4 Air content The standard test method (ASTM C 231) for air content by the pressure meter was t m pressure head, absorption by capillary suction, adsorption and desorption, and migratio on field. Laboratory investigation of the transport characteristics for FRC is an important aspect for the understanding of degradation mechanisms for environmental exposure. In this study, major transport properties including absorption, permeability, and chloride diffusion processes were only performed and evaluated for concrete mixtures containing each fiber type in an effort to investigate their influence on mass transport properties for FRC. 59

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3.5.2.1 Permeable pore space test ASTM C 642 is the s tandard test method for determion, t voids in hardened concrete. By using the values for mass ded in oven-dry ated mass after immersion, saturated mass after boiling, and immersed apparent mass, sorbed water into the specimen was calculated as follows to deine permeable ination of density, percent absorpt and percen etermin mass, satur the total ab term pore space: 100)( 2gp (3-1) where p = permeable pore space (%) 12ggg= bulk density, dry 3.5.2.2 SurfThis non-destructive laboratory test method (FM 5-578) assesses the electrical resistivity of water-saturated concrete surface and provides an indication of its permeability, but can cause ded electrically conductive materials such as reinforcing steel, cium nitrite, are present (FM 5-578, 2004). ere made on the top circular face of the specimens marking the 0, 90, 180, and 270 degree points along the circumference of the circle. The marks were extended along the longitudinal sides of the specimen serving as visual aids 1 g 2 = apparent density. This test approach does not include a determination of absolute density. Hence, such pore space as may be present in the specimen that was not emptied during the specified drying or was not filled with water during the specified immersion and boiling, or both, was considered impermeable and was not differentiated from the solid portion of the specimen for the calculations, especially those for percent voids. ace resistivity test misleading results when embed conductive fibers, and cal After moist curing, four indelible marks w 60

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during the resistivity reading. Small concrete blos remaining after cores were used to obtain resistivity measurements on fiber specimens. Top and sides of the small block surface were marked and measured. Experimental test set up for surface resistivity is shown as in Figure 3-8. ck A B the side of the specimen at the 0 degree mark. All the points of the array probe were in contact Figure 3-8. Surface resistivity test set-up. A) Cylinder specimen. B) Fiber specimen. A Wenner linear four-probe array with spacing of 1.5 inches was placed longitudinally on with the concrete. Resistivity measurements were typically obtained after 3 to 5 seconds or until a stable reading was obtained. This procedure was repeated for 90, 180, and 270 degree marks 61

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and the averacharacterize the permeability of the concrete based on surface resistivity per FM 5-578. Table 3-10. Surface resistivity-permeability ge resistivity for the set of samples was calculated. Table 3-10 was used to Chloride Ion Permeabilit y Surface Resistivity Test (k-cm) < 12 High Moderate 12-21 Low 21-37 Very Negligible > 254 Low 37-254 3.5.2.3 Permeability test The water permeability apparatus developed by Soongswang et al. (1988), which measures one dimensional flow into concrete, was used to measure the coefficient of permeability for each of the concrete mixes. A schematic diagram of the water permeability flow apparatus is shown in Figure 3-9. The Plexiglas ring on top of the specimen is a chamber which holds pressurized water. The bottom of the specimen was open to the atmosphere which creates a pressure gradient across the specimen and results in pressurized water flow. A pressure of 275.8 kPa (40 psi) was used for testing. The volume of water flow into the specimen was computed by reading the water level change of the manometer tube. A plot of the cumulative water amount versus time was drawn to determine the steady state flow condition. The coefficient of water permeability was measured from the net rate of inflow using the following expression based on Darcys law: PAHQKw (3-2) where Kw = coefficient of permeability in m/sec = density of water in Mg/m3 P = water pressure in Pa Q = net rate of inflow in m3/sec A = cross-sectional area of test specimen in m2. H = length of test specimen in m 62

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A B Figure 3-9. Water permeability test specimens. A) Schematic diagram. B) Test specimen. he capillary action is the main transportunderstanding of mass transport in concrete is necessary to evaluate its durability properties and service life. The standard test method for the determination of the rate of water 3.5.2.4 Absorption test The ingress of deleterious materials such as chloride and sulfate ions into concrete from tprocess of diffusion is relatively slow (Martys et al., 1997) in comparison to other transport properties like absorption. Therefore, it may be that mass transport of deleterious materials by mechanism for unsaturated concrete. The fundamental estimate absorption by hydraulic cement concrete in accordance with A STM C 1585 (2004) is used to Water Ou t flow Plexiglas Plate Plexiglas Ring Test Specimen Neoprene Gasket (2 in thickness x 4 in diameter) Water Inflow 63

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determine the effects of fiber and fiber ty pe. The absorption is determined by the increase in the ulting from capillary action of water as a function of time when only one surface of the specimen was exposed to water with sealed sides (candle wax) and top surface. The absorption is the change in mass divided by the product of the cross-sectional area of the test specimen and the density of water. For the purpose of this test, the temperature dependence of the density of water was neglected and a value of 0.001 g/mm3 was used. The absorption, I, considering permeable voids in the specimen was calculated as follows: mass of a specimen res padmIt (3-3) in grams, at the time t a = th2d = th setup of where I = the absorption (mm) m t = the change in specimen mass e exposed area of the specimen, in mm e density of the water in g/mm 3 The water transport into concrete by capillarity is controlled by the square root of time relationship. The initial rate of water absorption (mm/s 1/2 ) was defined as the slope of the line that is the best fit to I plotted against the square root of time (s 1/2 ). This slope was obtained by using least-squares, linear regression analysis of the plot of I versus time 1/2 A schematicthe capillary suction test is shown in Figure 3-10. A 100 50 mm cylindric al specimen was placee ater r the ater was blotted off with a dampened paper towel for each mass determination. d on the support device at the bottom of the pan, which was filled with tap water so that thwater level was maintained at 1 to 3 mm above the top of the support device. The absorbed wquantity was recorded at 1, 5, 10, 20, 30, 60, 120, 180, 240, 300, 360 min and once a day fofirst 3 days was recorded, and then 3 measurements at least 24 hours apart during days 4 to 7. The final measurement was recorded at the end of day 7. Any surface w 64

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A Water Level B FBulk diffusion test anism of chloride ions into concrete when table (Song et al, 2008) and differences in opp, 1995). The chloride diffusion testing was performed in accordance with NT BUILD 443 test method. Upon the completion of 28 days curing, test specimens were taken out of moisture cure and were sliced into two halves. After which, they were immersed in the Ca(OH)2 solution until the mass of the concrete stabilized. The specimen immersion for Ca (OH)2 solution was repeated after sealing the surfaces of the specimen with Sikadur 32 Hi-Mod epoxy. Subsequent to conditioning, the specimens were immersed in 16.5 percent sodium chloride solution in tanks for 365 days. As part of the exposure process, the is a photograph of the exposure tanks located at the FDOT State Material Office. Upon the removal of the specimens from the exposure tanks, the chloride profile was obtained grinding off material in layers parallel to the exposed surface. The surface chloride concentrations (Cs) obtained for each layer which was used to determine coefficients of diffusion (De). The coefficient of diffusion is calculated by fitting the equation to the measured chloride Candle Wax igure 3-10. Absorption test set-up. A) Schematic diagram. B) Testing specimens. 3.5.2.5 Diffusion process is the primary transport mech the moisture condition in the pore structure is s chloride concentration induce chloride movement, as opposed to the convective flow of capillarysuction or permeation (Kr solutions were replaced every 5 weeks. Figure 3-11 65

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contents by means of a non-linea r regression analysis in accordance with the method of least squar es fit. The solution to Ficks Second Law of Diffusion which is represented as follows: tDxeiss5.0where erfCCCtxC)(),( (3-4) C(x,t) = the chloride concentration, measured at the depth x at the exposure time t in mass % Cs = the boundary condition at the exposed surface in mass % Ci = the initial chloride concentration in mass % x = the depth below the exposed surface De = the effective chloride transport coefficient t = the exposure time erf = the error function. A B Figure 3-11. Exposure tank and specimen condition for bulk diffusion. A) Exposed tank. B) Unreinforced concrete is a brittle ml, but reinforcement of concrete with fibers will create a material with higher compressive, tensile, flexural and shear strength properties. The random distribution of short fibers may contribute to the load transferring mechanism through shear stresses at the fiber-hardened cement paste matrix interface. For a given mixture, the fiber volume fraction, fiber geometry, and fiber distributions have considerable effect on the mechanical properties of FRC (Beaudoin, 1990 and Bentur et al., 1 Testing specimens. 3.5.3 Mechanical Properties ateria990). 66

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This section describes the mechanical properties of FRC designed to evaluate effec ts of d fiber type on mechanical properties of FRC. Three different mechanical tests were l differences between unreinforced concrete and FRC: ting tension (ASTM C 496), pressure tension, residual strength (ASTM C 1399), and flexural performance of FRC (ASTM C 1609). 3.5.3.1 Compressive strength testing Compressive strength testing in accordance with ASTM C 39 was performed after 28 days of curing time as shown in Figure 3-12. The load was applied at a stress rate of 35 7 psi/s until he specimen. The ultimate compressive strength was calculated by dividing the maximum load by the average cross-sectional area as shown by the following equation: fiber an performed to investigate the physica compression (ASTM C 39), split failure of t 24Dpfc (3-5) where fc = ultimate compressive strength of cylinder, in psi ressive axial load applied to cylinder, in lbs der specimen, in inches. of compressive strength from three cylinders were taken as the compressive te. p = ultimate comp D = diameter of cylin The average values strength of the concre Figure 3-12. Test set-up for compressive strength 67

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3.5.3.2 Splitting tensile testing Three standard cylindrical 4 x 8 in test specimens were prepared to determine the splitting strengths (ASTM C 496-01) at 28 days. This was obtained directly from the load recorded busing a 600 kip capacity FORNEY testing machine. The setup for the splitting tensile tests is shown in Figure 3-13. y A B Figure 3-13. Test set-up for splitting tensile test. A) Test set-up. B) Loading condition. Before testing, the diameter and length of the each test specimen were determined to nearest 0.01 in. (0.25 mm) by averaging three diameters measured near the ends and the middle of the specimen and two lengths of the specimen on the two ends. The splitting tensile testing was performed in accordance with the ASTM C 496-01. Diametral lines were drawn on each end of the specimen using a suitable device to ensure that they were in the same axial plane, and then two pieces of hard wood measuring 0.25 0.75 8 in were placed 180 apart along the longitudinal axis of each cylinder, as shown in Fig. 3-13b. This was done to avoid any stress concentrations that might result along the line of application of the load. The load was applied failure of the specimen. The maximum applied load indited by the testing machine at failure was recorded. Tmputed as follows: continuously and without shock, at a constant rate within a range 100 to 200 lbs/sec until ca he splitting tensile strength was co 68

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lDPfst 2 (3-6) where fst = splitting tensile strength, in psi P = maximum applied load, in lbf l = length of cylinder, in inches D = diameter of cylinder, in inches. 3.5.3.3 Pressure tension testing Elastic behavior of hollow cylinder specimens based on the theory of lasticity helps to t. Timoshenko and Goodier (2004) represented the stress states in cylinder specimens with the radius R as shown in Figure 3-14 by following equation: e understand the stress states of pressure tension tes )()()()(3333333333330baRRbaPbaRaRbPiR (3-7) )(2)2()(2)2(3333333333330baRbRaPbaRaRbPit (3-8) where R = radius stress t = tangential stress b = outer diameter a = inner diameter P0 = outer pressure Pi = inner pressure. The radius and tangential stresses in the hollow container depend on a function of Radius (R). If Pi = 0, then 0PtR (3-9) The pressure tension test was developed by the British Research Establishments in the UK (Clayton et al, 1979) as shown in Figures 3-15 and 3-16 pressurizes the concrete specimen 69

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cylinder or core by means of an extna erlly applied gas pressure with a rubber ring between steel jacke turated an internal pore pressure develops in response to this applied pressure, acting equally in all directions. It is generally agreed that the maximum pressure of nitrogen gas is fundamentally equal to the tensile strength (Mindess et al., 2005; Clayton et al., 1979; Clayton, 1978; Boyd et al., 2001), though the failure mechanism is not perfectly understood. t and end ring to prevent leakage of pressurized nitrogen gas. This applied pressure acts only upon the curved surface of the specimen, which is positioned within a pressure sleeve, sincethe ends of the cylinder project outside the pressurized area. As long as the specimen is sa Figure 3-14. Stress state in hollow cylinder under internal or external uniform pressure P 0 P i b a t R R 70

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71Figure 3-15. Nitrogen gas tension test and stress state. A) Overview. B) Second view. C) Stress state. (after Mindess et al., 2005). Concrete cylinder Socket head bolt Steel J acket A End ring Nitrogen gas inlet Rubber O ring B Pressure C D 1.5 D Figure 3-16. Pressure tension testing equipments

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3.5.3.4 Residual strength testing Average residual-strength (ARS) measurement for fiber-reinforced concrete as specified in ASTM C 1399 was performed for the beam specimens subsequent to pre-cracking with the steel plate at the bottom of the beam to control the rate of deflection as shown in Figure 3-17. A B Figure 3-17. Test setup for measuring residual strength by using deflection gage and yoke. A) cified, the rate of cross-head movement was set at 0.65 0.15 mm/in (0.025 0.005 ion as and were placed on top of the steel plate to be loaded. The reason for the steel plate is to g the initial loading period to limit the expected high rate of acking. The beam specimen was placed on the steel plate with e lower bearing blocks. The deflection gage Before inducing crack with steel plate. B) After crack. As spe n/min). Then, the degraded beams were turn to their sides with respect to their positi molded aid the beam specimen durin deflection of the beam upon cr support yoke and the steel plate was centered on th 72

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was adjusted and loading was applied until a deflection of 0.5 mm (0.02 in) was reached in combination with the steel plate. If cracking had not occurred after the beam reached a specified deflection, the test was considered invalid. After removal of the steel plate, the crack induced beam and deflect in gages were adjusted on the lower bearing blocks. Loading was applied to cracked beam at the specified rate used for the initial loading and the test was stopped at a deflection of 1.25 mm (0.05 in.). The average residual strength was calculated using the measured loading at reloading defections of 0.5, 0.75, 1, and 1.25 mm (0. 02, 0.03, 0.04, and 0.05 in.) as follows (Figure 3-18): kPPPPARSDCBA )4/)(( (3-10) where k = L/bd2, mm-2 (in-2) ARS = average residual strength, MPa (psi) PA+PB+PC+PD = sum of recorded loads at specified deflection, N (lbf) L = span length, mm (in) b = average width of beam, mm (in) d = average depth of beam, mm (in). Figure 3-18. Load vs. deflection curve for residual strength measurement 0.250 Loa d N Net Deflection, mm 0.500.751.001.25PA PB PC PD Initial Loading Curve Reloading Curve 73

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3.5.3.5 Flexural performanc e testing g The test method specified in ASTM C 1609 evaluated the flexural performance of fiber-reinforced concrete using parameters derived from the load-deflection curve obtained by testin a simply supported beam under third-point loading as shown in Figure 3-19. Figure 3-19. Test set-up for measuring flexural performance of FRC with yoke The test specimens after environmental conditioning were turned on their side with respeto the position as cast when placing on the support system. Then, support yoke and deflection gage were arranged to obtain net deflection. The load was applied at the rate of increase of net deflection within the range 0.05 to 0.1 mm/min (0.002 to 0.004 in./min) until a net deflection ofL/600 was reached. After that, the rate of increase of net deflection was within the range 0.05 to0.2 mm/min (0.002 to 0.008 in./min) until reaching net deflection of L/150. Test results were discarded when the crack initiated outside of the middle third of the span. The first-peak load was that value of load corresponding to the first points on the load-deflection curve where the slope is zero was determined as well the corresponding deflection value at that point. The first-peak strength (f ct 1 ) using the first-peak load (P 1 ) was calculated by following formula for modulus of rupture: 21 B DPLf (3-11) 74

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where f 1 = the strength, MPa (psi) P = the load, N (lbf) L = the span length, mm (in.) B = the average width of the specimen, mm (in.) average depth of the specimen, mm (in.). ad corresponding to the point on the load-deflection curve that oint deflection, ing deflection (p) value at that point. Then, the peak strength was calculated. The residual loads (P4, 0.02 and P4, 0.08) at span/600 and span/150, as well the corresponding residual strengths were calculated. Finally, the total area (T4, 0.08) under the load-deflection curve up to a net deflection of span/150 was calculated. Examples for parameter calculations for different Flexural curves are represented in Figure 3-20. D = the The peak load was that value of lo corresponds to the greatest value of load (P p ) obtained prior to reaching the end-p which was determined as the correspond Net Deflection L/600 1 L/150 0 Load P1 P4 0.02P4, 0.08 Pp p a) First-peak load equal to peak load b) Peak load greater than first-peak load Figure 3-20. Examples of parameter calculations for different flexural curves 75

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3.5.4 Steel Bar Corrosion The steel bar corrosion testing in accordance with ASTM G 109 was used to evaluate teffect of fibers on resistance to corrosion of steel bars embedded in fiber reinforced concrete. The fibers used in this test were cut into 0.5 in. in length by considering the size of steel bar in concrete structure. Two specimens were prepared and cast for control and each fiber type for concrete classes II and V. The steel bars were sand blasted to near white metal. One end of eachbar was drilled/tapped and a stainless steel screw and two nuts were attached. Each end of the steel bar was taped with electroplaters tape so that a 200 mm (8 in.) portion in the middle ofbar was left exposed. A 90 mm (3.5 in) length of neoprene tubing was placed over the electroplaters tape at each end of the bar. The steel bars and titanium bar representi he the ng corrosion pFigure 3-20b and ncrete was placed and consolidated. Upon removal from the moist room after 28 days te specimens was hand-wire brushed and dried for two weeks tive humidity room before applying a plastic dam with an epoxy sealer. The plastic ng, with a height of 50 mm (2 in) was placed on the top suled specimens were stored in a 50% relative humidity (RH) environment for an additional two weeks and then testing was started. The plas6.5% NaCl solution and the sp at Immersion in a temperature controlled room. After two weeks, the r two weeks. This cyclic wetting and drying was repeated until sign otential of the bars were placed in the mold (11 6 4.5 in) as shown in then co curing, the top surface of the concre in a 50% rela dam, 75 mm (3 in.) wide and 150 mm (6 in) lo rface with the outside of the plastic dam sealed with silicone caulk and epoxy sealer. The sea tic dam was filled with 1 ecimens were stored solution was vacuumed off and allowed to dry fo ificant steel corrosion was detected. The current and corrosion potential of the bars were monitored once every day. The test set-up for corrosion is shown in Figure 3-21. The 76

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ratio of total integrated current of the damaged specimens to that of the control and time the test ended was calculated. The total integrated current is: ]2/)()[(111jjjjjjiittTCTC where TC = total corrosion (coulombs) t (3-12) A j = time (seconds) at which measurement of the macrocell current is carried out i j = macrocell current (amps) at time, t j B Figure 3-21. Test set-up for steel bar corrosion. A) Schematic diagram. B) Mold and test set-up. 16.5% NaCl TTiittaanniiuumm BBaarr ( ( c c o o r r r r o o s s i i o o n n p p o o t t e e n n t t i i a a l l ) ) R R VV 77

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3.5.5 Ultra Pulse Velocity (UPV) Ultra Pulse Velocity (UPV) specified in ASTM C 597 was performed to indicate any changes of the properties in FRC to estimate the severity of deterioration of beams subsequent to environmental exposure. Pulses of longitudinal stress wave are produced by an electro-acoustical transducer that is held in contact with one surface of the beam. After traversing through the beam, the pulses were receivconcrete (Bungey, 1989). The pulse velocity, V, of longitudinal stress waves in concrete mass is related to its elastic properties and density according to the following relationship: ed and converted into electrical energy by a second transducer located a distance from the transmitting transducer. The degree of saturation of the concrete affects the pulse velocity. The pulse velocity in saturated concrete may be up to 5% higher than in dry )21)(1( )1(E V (3-13) where E = dynamic modulus of elasticity = density. The pulse velocity was calculated as follows: (3-14) where V = pulse velocity, m/s T = transit time, s. 3.5.6 Scanning Electron Microscopy (SEM) interfacial zone between the fiber and the hardened cement paste matrix as a result of chemical = dynamic Poissons ratio L = distance between centers of transducer faces, m Semi-quantitative chemical analysis for Scanning Electron Microscopy (SEM) with Energy Dispersive Spectrometer (EDS) were performed to observe microstructure changes in the TLV/ 78

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reaction during environmental exposure. Two Class II concrete specimens per fiber type subjected t o limewater and saltwater immersion were chosen and analyzed. The specimen sliced from the fractured beam was in a saturatedsed saw because epoxy-impregnated sawn polished surfaces general used to prepare concrete samples can cause damage in the form of cracking patterns or crystals (Stella, 1995). Before examination, specimens were coated with a thin carbon film by sputtering with low deposition rate. Secondary Election (SE) images, which element analysis providing elemental compositions marked on a chart, where specifically Finally, a dot map indicating the distribution of a particular element was created. 3.5.7 Carbonation The depth of the carbonation was determined by fracturing or chipping the beam specimens after flexural beam testing. After splitting one face of the specimen, the specimen was cleared of dust and loose particles and then phenolphthalein indicator solution was sprayed on the fractured surface. The phenolphthalein indicator changes color at a pH of 9.0 to 9.5. The depth of carbonation was determined by measuring the area of the broken surface which does not turn purple after spraying. condition due to long term exposure. Unpolished urfaces were prepared by using a diamond blad are capable of displaying the morphology of the microstructure were obtained, as well as X-ray selected elements are recognized on a continuous spectrum according to the position of its peak. 79

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CHAPTER 4 ENVIRONMENTAL EXPOSURE 4.1 Introduction This chapter is divided into three sections: degradation mechanism of concrete structure in seawater; environmental exposure; and expected deterioration mechanism during conditioning. 4.2 Deterioration of a Concrete Structure in Seawater Mehta (1980) determined that the type and severity of degradation is not consistent zones, which are represented in Figure 4-1. through concrete structural elements based on the environmental exposure conditions. The portion of the concrete structure exposed to seawater is typically separated into three kinds of Figure 4-1. Sc hematic diagram for degradation mechanism of a concrete structure exposed to seawater. (From P. K. Mehta, 1980 and Mehta et al., 2005). 80

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The first part, which is above the high-tide line, is directly exposed to atmospheric air, ning sea sabe mnerable to cr steel brosion or rom freezing/thawage actionern climates. The second part, in the tidal susceptible to cracki spalling from the cyclic wettindrying action, and frost action. Tncrete in the zone is also subject to materials degradation due to chemical decoion of ceme, and erosion due to impact of wave action. The l2+een ), soluble in sea water, lead to materials loss or weakening. The formation of e expansion and cracking of te: ))(OHOHaOHOH222)()( winds contai lts and will ore vul acking due to ar cor spalling f ing dam in north zone, is ng and g and steel corrosion he co tidal or loss mposit ent past ower part, which is the submerged zone under low tide line, is vulnerable to strength or material loss resulting from the reaction of chemical ions (CO 2 sulfate, chloride, Mg) betwsea water and cement paste. The chemical reactions between magnesium salts, typically contained 3200 ppm MgCl 2 and 2200 ppm MgSO 4 and Ca(OH) 2 produce CaCl 2 and gypsum (CaSO 4 2H 2 O ettringitte (3CaOAl 2 O 3 3CaSO 4 32H 2 O) by MgSO 4 also causes th concre 2CaCl (4-1) 22 2CMgCl (Mg OH CaSO4 Mg2 CaMgSO4 -2) CaSCOHOAlOH32232233)18)( (4 HO2432 OAlaO2 OHMg( CaSO4 CaO3 CaMgSO4 O (4-3) Carbon dioxide dissolved in sea water contributes to the chemical decomposition of hardened cement paste. Small quantities of carbon dioxide are normally dissolved from absorption of atmospheric CO2, but highly carbonated sea water due to decaying organic matter drops the pH of sea water less than 7 or less and the chemical reactions produce bicarbonate of calcium or gypsum. Both chemical products are soluble in sea water and cause loss of material or weakening of cement paste: 81

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232322)()(2HCOCaOHCaCOOHCaCOCO (4-4) OHCaSOOxHCaCOOAlCaOOHCaSOOAlCaOOHCaCO2423322432223183)( (4-5) The dominant transport mechanism of solutions into partially saturated condition is capillary suction. The chemical ions within the solutions, deposit into pore spaces by the evaporation of as it undergoes cyclic wetting and drying. Hong and Hooton (1999) studied the penetration of chloride ions into cover concrete to evaluate the effects of wet-dry cycles with NaCl solution. The research found that the rate of chloride movement into concrete was as developed between the depth of chloride penetration and the square root of the number of cycles for the outer 10 mm of concrete cover where absorption is the primary transport mechanism. 4.3 Environmental Exposure Previous studies (Al-Tayyib et al.; 1988, Balaguru et al.; 1986, Mangat et al., 1985) exposed undamaged concrete blocks to environmental conditioning, thus limited fiber exposure. However, this study examined the resistance of FRC exposed to both a virgin un-cracked condition and a pre-cracked condition as explained per ASTM C 1399 testing. research. The first exposure condition completely immersed fiber reinforced concrete in simulated sea water with 5% chlorides and 1% sulfate ions at 90F water temperature for 21 month exposure period. High salt concentration in pores accelerated transport of chemical ions into concrete and also potential damage due to the hygroscopic effect of the salt in the pore system (Kropp et al., 1995). The composition of simulated sea water is summarized in Table 4-1. increased as drying time increases. A relationship w Three exposure conditions were created for the evaluation of concrete specimens in this 82

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A second exposure condition provided cyclic wetting and drying where the beam specimens were immersed six hours in seawater and dried at room temperature for another six hours for duration of 21 months. Water was pumped automatically from one tank to another tank after wetting periods. While the specimens were immersed, the water was circulated through the bath. Wet/dry cycling tends to accelerate accumulation of deleterious materials in the pore system such as chloride and also may induce cracking in concrete. Absorbed chloride ions during wetting period remain in theying. Therefore, tion near-surface of concrete accelerates mass transport of chloride ions and salt crystallizatidess pore system when water evaporates upon dr in creased salt concentra on in the pore system might cause micro-cracking. Repeated wetting and drying accelerates sulfate attack and salt crystallization in the pore during drying periods causing expansive forces in the intertidal zone where additional damage action can take place (Minet al., 2003). Table 4-1. Composition of simulated seawater Ocean Salinity (35g/1000g) Simulated Salinity (115g/1000g) Constituent Percentage PPM Percentage PPM Chloride 55.04 19,350 43.58 50056 Sodium 30.61 10760 27.47 31556 7.68 2710 8.41 9661 MagnCalciumTotal 99.28 34920 81.93 94117 Sulfate esium 3.69 1290 2.16 2482 1.16 410 0.16 184 Potassium 1.10 400 0.15 176 The third conditioning solution exposed beam specimens to swamp water. The swamp water solution had a pH 4.5 controlled by the addition of vinegar in an effort to simulate the swamp environment typical to the state of Florida. The flow chart for experimental program and numbers of specimens in the environment conditioning are summarized in Table 4-2 and Figures 4-2 and 4-3. 83

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Table 4-2. Beam specimens exposed to environmental exposure Lime water Lime water Salt water Salt water Swamp water Mix n Type Immersion Wet/Dry Immersion Wet/Dry Immersio PC-II (V) 10 (10) 10 (10) 10 (10) 10 (10) 10 (10) PP-II (V) 15 (15) 15 (15) 15 (15) 15 (15) 15 (15) PVAII (V) 15 (15) 15 (15) 15 (15) 15 (15) 15 (15) Cell-II (V) 10 (10) 10 (10) 10 (10) 10 (10) 10 (10) Steel-II (V) 15 (15) 15 (15) 15 (15) 15 (15) 15 (15) Environmental ere conditioni) Schematic d for beam condition in tank. B) Exposure Tanks. C) Beam Aent. D) Swaersion. Figure 4-2. Flow chart for experimental program A Figure 4-3. xposu ng. A iagram rrangem mp water imm Wood Cover Heater Spec imen Circulation Pump Mix t yp e S p ecimen condition Ex p osure condition Ex p osure time PC-II (V) PP-II (V) PVA-II (V) Steel-II (V) Limewate r -Immersion Saltwater Immersion Limewater W/D Saltwater W/D Un-cracked beams Un-cracked beams Pre-cracked beams Swampwater Immersion 32C 32C/5% Cl 32C/4.5 pH 32C 32C/5% Cl 40C 40C/7% Cl 40C/4.5 pH 40C 40C/7% Cl 21 months 21-27 months. 84

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B C D (b) Exposure tanks and beam arrangement Figure 4-3. Continued Development of New Wet/Dry Condition System: Water transfer into beam specimens based on preliminary test results. However, the relatively high humidity in the laboratory resulted in very little amount of moisture movement of about 1 to 3g in the beam specimens. This was not enough to promote certain types of degradation such as corrosion or to accelerate cracking by increasing the salt concentration in the pore network from the surface layers during 12 hours cyclic wetting and drying period. Thus the experiment was redesigned to reconcile the problem. An extensive amount of work was done to identify and design a system that would result in significant drying of specimens when not submerged, thereby more closely simulating wet/dry subjected to field conditions was determined to be between 30g in March and 50g in August 85

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conditions in the field, which cause much greater concentration and penetration of ions and potential for corrosion. After several trials involving dehumidifiers and different types of heating systems, an appropriate system was identified and installed as shown in Figure 4-4. The system involves the use of specially designed heater/blowers combined with a reduced volume tank. The heater/blowers force much greater amounts of moisture to be carried out of the tank by the hotter air, which results in much drier specimens in less time. However, 6 hours for wetting (90 F) and 6 hours for drying (100~135 F) conditioning, even with the heater/blowers, were still not enough to induce significant damage area on the fracture surface to evaluate fiber resistance on postcracking failure. Therefore, the wetting and drying cycle times were increased to 7 days for wetting and 7 minimize carbonation rather than oven conditionig. The final depth of absorbed water for 7 damage of approximately about 50% of volume of beam. As a result of the redesign of the drying system and the increase of the cycle time, the total amount of water transferred was 100 to 150g. Another change in the experiment per the new wet/dry conditioning was the increase of the chloride concentration of the solutions to 7% and the water temperature was increased to 105F. The redesigned composition of simulated seawater is summarized in Table 4-3. The moisture transfer test results with increased wetting and drying time with new conditioning system is shown in Figures 4-5, 4-6, 4-7, and 4-8. Additional environmental exposure for all specimens was continued from 21 months to 27 months. days for drying to maximize moisture gain and loss with minimizing micro-damage and also n days wetting was determined to be 12.5 mm (0.5 in.) from the concrete surface, which induced 86

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Table 4-3. Redesigned composition of simulated seawater Ocean Salinity (35g/1000g) Simulated Salinity (115g/1000g) Constituent Percentage PPM Percentage PPM Chloride 55.04 19,350 46.22 70525 Sodium 30.61 10760 29.13 44460 Sulfate 7.68 2710 6.55 9990 Magnesium 3. 2592 Calcium 1.16 410 0.17 260 Potas 69 1290 1.70 sium 1.10 400 0.16 247Total 99.28 34920 83.93 128074 A Fan B C Figurblower/heater. C) Schematic diagram for new wet/dry system. e 4-4. New wet/dry environmental exposure conditioning. A) Exposure Tanks. B) Air Air Hot Ai r Moisturized Air Heating Coils HeatCoil 87

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-50-30-100271522293643Days (g ) -170-15030 -1-90-70Wr Transfer PC-II -110ate PP-II PVA-II Cell-II Steel-II Figure 4-5. Moisture movement with new wet/dry conditioning for limewater wet/dry for Class II concrete -170-150-130-110-90 -70-50-30-1001234567891011121314222936435Dayster Transfr (g 0Wae ) PC-II PP-II PVA-II Cell-II Steel-II Figure 4-6. Moisture movement with new wet/dry conditioning for saltwater wet/dry for Class II concrete 88

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-170-150 -130 -110-90-70-50-30-1010012379152229364350DaysWater Transfer (g ) PC-V PP-V PVA-V Cell-V Steel-V Figure 4-7. Moisture movement with new wet/dry conditioning for limewater wet/dry for Class V concrete -170-150-130-110-90-70-50-30-1001237915222936435DaysWater Transfer (g 0 ) PC-V PP-V PVA-V Cell-V Steel-V Figure 4-8. Moisture movement with new wet/dry conditioning for saltwater wet/dry for Class V concrete 89

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4.4 Dechanism The expected deterioration mechanisms for salt water immersion, cyclic wetting and drying, and acidic solutions are summarized in Figure 4-9. Sulfate ions in salt water can attack the hydration products of cement paste, resulting in the degradation of the paste itself (Mindess et al., 2003). When the amount of CA is equal to or less than 5% in Portland cement, and the gypsum is approximately 5%, the hydration reaction converts all of the C3A to ettringite terioration Me 3 ( 3233HSAC ) with the hydration of Cr, the AASHTO cement type I 3 A with water and gypsum. Howeve I used in this study contains 6.16% C 3 A so that monosulfate hydrate ( 18123HSAC) can be produced as the additional hydration product. The chemical reactions with C 3 A and monosulfate hydrate ( 18123 HSAC) when the cement paste comes in contact with SO42convert to ettringite ( 3233HSAC ) in the presence of CH (Cohen et al, 1993; Tian, 1998): 3236218124)1610(2HSACHHSCHSAC (4 -6) 323623263HSACHHSCAC (4-The formation of ettringite related to the needle-like formation of the crystal can produce expansion forces and cracks in concrete. The formation of cracks influences t 7) ransport pathways resulting in the acceleration of chemical ions i loss when the pH decreases to below 12.5 whereas the dissolution of C-S-H gel begins at below pH 8.8 (Metha, 2005). The characteristics, by essentially providing large nto concrete. Sulfate attack also generates progressive damage resulting in the loss of strength andof mass due to degradation of the cement hydration products. The most commonly available hydration products of cement paste, CH and C-S-H gel, may be transformed to gypsum as a result of sulfate attack (Cohen, 1993). The dissolution of CH happens 90

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91sulfate attack resulting from Magnesium sulfates is typically a more aggressive attack due to the destruction of the C-S-H and the calcium sulfoalumiates (Mindess et al, 2003): xSHMHHSCaqSMHSC233)(32323 (4-8) 3212434)(3AHMHHSCaqSMHSAC (4-9) The steel fibers distributed in concrete are naturally protected by the protective oxide film on the fiber surface due to the presence of alkalinity of the concrete in pore water. However, chlorides in pore space cause a local breakdown of the passivation film on the steel fibers, so that the localized corrosion can subsequently occur and increased volume from active corrosion leads to expansion forces or micorcracking in the concrete (Mindess et al., 2003). The degradation of FRC by acidic solutions will result in a different deterioration process. The hydrogen ions in roxide by causing efflorescence and increasing permeability (Mehta et al., 2005). The C-S-H gel, naturally weak due to its micro-porosity structure may also be dissolved by acid attack when the hydrogen ions are highly ment paste, limestone, and fibers exposed to acidic solutions will be expected to have dissolution or loss of mass during acid attack. Figure 4-9. Expected deterioration mechanism solutions will accelerate the leaching of calcium hyd accumulated. In addition, the hydration products of ce Sulfate Attac k Steel Corrosion Chloride Attac k Acid Attac k Gypsum/Ettringite Formation Expansion/Crack Decomposition of CH/CSH Additional Corrosion Reaction Ca(OH)2 Cement Paste Aggregate Fiber M g SO 4 Attac k Expansion Crack Surface Dissolution/Leaching Transport Mechanism

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CHAPTER 5 FINDINGS AND ANALYSIS 5.1 Introduction This chapter describes and discusses test results of laboratory investigations of fresh properties, transport properties, mechanical properties, and evaluation of degraded specimens on beam tests based on visual inspection, permeable pore space change, carbonation, and SEM analysis. 5.2 Fresh Properties Test Results A comprehensive summary of test results can be found in appendix A (Tables A-1 and A-2). A more succinct summary of findings is presented in the sections below. 5.2.1 Slump Test Results d 5-2. These figures ility due to the introduction of fibers. The reduction range for eachl ixture. p loss, the longer the time to make the fiber mixes flow, which is consistent with the greater amount of energy required. The test results for both Concrete Classes are shown in Figures 5-1 an demonstrate the reduction of fresh mix workab fiber was 4.5-7.0 in. for PP, 4.25-5.50 in. for PVA, 1.25-3.50 in. for cellulose, and 2.50-4.75 in. for steel fibers. It was noted that the introduction of cellulose fiber for concrete Class II resulted in the lowest slump loss (reduction in slump relative to the contromix) implying non-uniform fiber distribution or fiber balling in the m 5.2.2 Inverted Slump Cone Test Results The results of inverted slump cone time are shown in Figure 5-3. The addition of fibers definitely requires more time to make the stiffer fiber mixtures flow. The cellulose fibers indicated the lowest time, one again indicating the fibers non-uniform distribution within the mixture. It is noted that the higher the slum 92

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0246810Slump (in) Without Fiber5.756.506.507.503.25 With Fiber01.001.505.750.75PCPPPVACellSteel Figure 5-1. Slump test results for Class II concrete 9 78 0123456umin) 10Slp ( PCPPPVACellSteel Without Fiber3.257.758.507.507.00 With Fiber02.004.254.002.50 Figure 5-2. Slump test results for Class V concrete 93

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020406080100 120 Inverted Slump Time (s) Concrete Class II15 99 85 10 87 Concrete Class V32 78 67 16 59 PCPPPVACellSteel Figure 5-3. Inverted slump cone time test results for Classes II/V concrete 5.2.3 Vebe Test Results The test results of Vebe time are shown in Figure 5-4. Although it requires less time than the inverted slump cone test, the test results are very similar to that of inverted slump cone time (Figure 5-3). It was observed that there was significant decrease of workability of the concrete upon the addition of PP, PVA, and hooked Steel fibers. Figures 5-5 and 5-6 indicate that there were slight differences in the air content resulting from the addition of PP, PVA, cellulose and steel fibers. However, these small differences are likely within measurement error and do not appear to be sufficient to justify any observed differences in concrete performance. 5.2.4 Air Content Test Results 94

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012345678910Vebe Time (s) Concrete Class II27619 Concrete Class V46425PCPPPVACellSteel Figure 5-4. Vebe time test results for Classes II/V co ncrete 01 3456ntent%) 2r Co Ai ( Without Fiber5.104.704.203.704.00 With Fiber03.204.203.902.80PCPPPVACellSteel Figure 5-5. Air content test results for Class II concrete 95

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01 2Ai 345r Cont% 6ent () Without Fiber3.403.002.702.702.80 With Fiber02.902.003.402.40PCPPPVACellSteel Figure 5-6. Air content test results for Class V concrete 5.2.5 Relationships between Workability Tests The relationship between conventional slump values and inverted slump cone time is presented in Figure 5-7. As expected, the slump was inversely proportional to the inverted slump cone time and the fibers with lowest slump require longer times. Similar test results for Vebe between the inverted slump cone and Vebe time is presented in Figure 5-9. These results are completely consistent with fresh property test results reported by ACI committee 544. re more accurate for measuring bslump test, but the inverted cone test exhibited the greate time versus slump are shown in Figure 5-8. The relationship illustrating direct proportionality Both inverted slump cone and Vebe time test methods a workaility of FRC than the conventional st sensitivity between workability of different fiber types and involves less expensive equipment. Therefore, the inverted slump cone test is recommended for measurement of workability of FRC. 96

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y = 1.90 x2 29.74 x + 118.53R2 = 0.92020 6080p Cone T 40rted Sl 100120me (s) 01234567Slump (in)Inveumi Class II Class V Figure 5-7. Inverted slump cone time vs. slump y = 0.24 x2 2.90 x + 10.13 R2 = 0.95 02681001234567Slump (in) Time (s) 4Vebe Class II Class V Figure 5-8. Vebe time vs. slump 97

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120 Class II Class V 80ne Tme ( y = 12.34 x 1.98R2 = 0.844060rted Slump C 100eois) 0200246810Vebe Time (s)Inv formed examining the effects of fiber and fiber type on transport characteristics of hardened concrete. Permeable pore space, permeability, absorption and chloride diffusion tests were used as representatives of the hardened physical transport properties. A comprehensive summary of test results can be found in the Appendixes B through F. A more succinct summary of findings is presented in the sections below. 5.3.1 Permeable Pore Space Test Results The permeable pore space changes due to the addition of different types of fibers to concrete were tested at 28 days. Test results for permeable pore space from the addition of fibers are shown in Figures 5-10, 5-11, and 5-12. The addition of PP and PVA fibers for both concrete Classes slightly increased permeable pores in concrete compared with both control mixes and control specimens cast before adding fibers. On the other hand, steel fiber mixes showed reduced Figure 5-9. Inverted slump cone time vs. Vebe time 5.3 Transport Property Test Results An experimental program was per 98

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permeable pores for Class II concrete, but no effect or a slight increase in permeable pores for the hardened cement paste concrete. Generally, the addition of fibers in concrete had a small effect on an increase of permeable pore space. Class V concrete. However, cellulose fibers showed no significant effect on permeable pores in 10111213141516Permeable Pore Space (%) Without Fiber With Fiber Without Fiber13.8013.1413.4612.96 With Fiber14.2613.5513.5612.12PPPVACellSteel Figure 5-10. Permeable pore space for Class II concrete without/with fiber 16 1415 Spa (% 10111213Permeable Po rece) Without Fiber With Fiber PP Without Fiber12.3212.9012.5513.18 With Fiber12.7713.6012.2213.04 PVACellSteel e 5-11. Permeable pore space for Class V concrete without/with fiber Figur 99

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16 1415 Space (%) 10111213Permeable Po re Concrete Class II Concrete Class V Concrete Class II12.9714.2613.5513.5612.12 Concrete Class V12.1912.7713.6012.2213.04 PCPPPVACellSteel Figure 5-12. Permeable pore space for Classes II/V concrete 5.3.2 Surface Resistivity Test Results Surface resistivity tests were performed for mixes with different types of fibers at the following times: 28, 56, 91, 182, 364, 540 and 730 days of 100% humidity curing. The effects of fiber and fiber type on penetration of chloride ions based on resistivity results are summarized as follows: Figure 5-13 shows surface resistivity measurements for Class II concrete. The surface resistivity of PP, PVA and cellulose fiber mixtures sharply increased after 91 days curing period and peaked at 1 year. After 1 year, the resistivity for permeability decreased and appeared to level out after 540 days. Among the fiber types, steel fibers, which are electrically conductive, had the lowest surface resistivity. Figure 5-14 shows surface resistivity measurements for Class V concrete. There were no sharp increases in the surface resistivity of PP and PVA. Resistivity of cellulose fibers peaked at 1 year. Once again, steel fibers showed the lowest surface resistivity. All fiber mixtures including both concrete Classes showed high possibility for chloride ion permeability from concrete surface according to the criterion indicated in Table 3-10. 100

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024681012141618200100200300400500600700800Time (Days)Surface Resistivity (K-cm) PC-II PP-II PVA-II Cell-II Steel-II Figure 5-13. Surface resistivity for Class II concrete 024681012 1416m) 18200100200300400500600700800Time (Days)Surface Resistivity (K-c PC-V PP-V PVAV Cell-V Steel-V Figure 5-14. Surface resistivity for Class V concrete 101

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5.3.3 Permeability Test Results The calculated water permeability coefficients of each kind of FRC mixture on hardened concrete at 28 days of age were examined to determine the effects of fiber and fiber type on the permeability characteristics of FRC. Test results are summarized as follows: Figures 5-15 and 5-16 indicate the effects of water permeability for with/without fiber in the same mixture. The addition of PP and PVA fibers for both concrete Classes showed no significant effect on coefficient of permeability. Among the fiber types, the steel fibers showed the highest reduction in water permeability for Class II concrete. Figure 5-17 shows the effect of fiber type on permeability for each concrete Class. The addition of polypropylene fibers showed no significant effect on coefficient of water permeability for both concrete Classes. The incorporation of polyvinyl alcohol fibers into the mixture showed no effect on water permeability for Class II concrete, but exhibited some reduction for Class V concrete. Among the fiber types, introduction of hooked-end steel fibers resulted in the greatest reduction for both concrete Classes. Among the fiber types, the use of hooked-end steel fibers showed the most consistent fibero water permeability in concrete. The addition of cellulose fiber generally showed higher permeability, which implies non-uniform distribution of fibers in concrete. results in comparison with control mixes and control specimens prepared before adding and has the highest resistance t 0.00.30.50.81.01.31.51.82.0Kw (x10-11 in/s) Without Fibe r With Fibe r Without Fiber1.291.001.711.54 With Fiber1.221.171.350.94PPPVACellSteel Figure 5-15. Coefficient of permeability for Class II concrete with/without fiber 102

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0.00.30.50.81.01.31.51.82.0Kw (x10-11 in/s) Without Fiber With Fiber Without Fiber1.060.780.940.73 With Fiber0.860.760.940.69PPPVACellSteel Figure 5-16. Coefficient of permeability for Class V concrete with/without fiber 0.00.30.50.81.01.31.51.8 2.0 Kw (x10-11 in/s) Concrete Class II Concrete Class V Concrete Class II1.191.221.171.350.94 Concrete Class V0.890.860.760.940.69PCPPPVACellSteel Figure 5-17. Coefficient of permeability for Classes II/V concrete 103

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5.3.4 Absorption Test Results The absorption rate changes due to the addition of fiber and fiber type were examined at 28 days curing. Test results are summarized as follows: Figure 5-18 presents typical examples of absorbed water versus square root of time for each mixture. The absorption rates for each Class of concrete were linearly proportional to square root of time. Among the fibers, PVA and hooked-end steel fibers showed the best resistance to capillary action for each concrete Class. However, PP fibers for both concrete Classes indicated the fastest rate of absorption for both initial and secondary time periods compared to the control and other fibers. Figures 5-19 and 5-20 compare absorption rate changes between mixtures with and without fiber. The addition of PP fibers showed significant increase in absorption rate for both concrete Classes. The addition of PVA fibers slightly increased the absorption rate for Class II concrete, but showed no significant change for Class V concrete. The use of cellulose fiber slightly increased capillary action rate for both concrete Classes. The addition of steel fibers showed no significant effect on Class II concrete, but indicated a higher absorption rate for Class V concrete. ype on absorption for each concrete Class. The addition of PP fibers showed a significant increase in absorption rate for both concrete fibers reduced the absorption rate for both The addition of PP fibers, which showed greater absorption than other fibers, significantly r into concrete. The elongated interfacial transition zone from the addition of PP fibers, which are relatively thin and long and hydrophobic in the Figures 5-21 and 22 show the effect of fiber t Classes, but the incorporation of PVA and steel concrete Classes. accelerated mass transport of wate nature might act as a route of ingress for mass transport of water between the fiber andhardened cement paste matrix. However, the addition of PVA and steel fibers generallyshowed higher resistance to mass transport of water than control specimens, implying relatively strong bonding which blocks water travel between the fiber and the hardened cement paste matrix. However, the effect of cellulose fibers in absorption was not clear because of inconsistent test results. 104

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048 12 I (m 16010020030040050060070080090010001100Time (sec0.5)Absorptionm) 20 PC-II PP-II PVA-II Cell-II Steel-II A 00100200300400500600700800900100011000.5 481220Time (sec)sorption I (m 16m) Ab PC-V PP-V PVA-V Cell-V Steel-V B Figure 5-18. Absorption vs. time for Classes II/V concrete. A) Classconcrete. II concrete. B) Class V 105

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0.000.01 0.04 Without Fiber With Fiber 0.03 Ratemm0.5) 0.02ptio Inl Arn (/s itiabso Without Fiber2.29E -021.81E-022.24E-022.20E-02 With Fiber2.54E-021.77E-022.39E-021.94E-02 PPPVACellSteel A 0.000.01 0.020.04bsoptionatemm/5) 0.03Secondary Ar R (s0. Without Fiber With Fiber Without Fiber1.45E-021.03E-021.58E-021.36E-02 With Fiber1.81E-021.26E-021.65E-021.39E-02PPPVACellSteel B Figure 5-19. Absorption rate for Class II concrete with/without fiber. A) Initial absorption rate. B) Secondary absorption rate. 106

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0.000.010.020.030.04Initial Absorption Rate (mm/s0.5) Without Fiber With Fiber Without Fiber1.08E-021.27E-021.20E-021.26E-02 With Fiber2.03E-021.35E-021.38E-021.55E-02PPPVACellSteel A 0.000.010.02 0.03te (m 0.04Secondary Absorption Ram/s0.5) Withut Fiber o With Fiber Without Fiber4.82E-031.02E-026.62E-036.81E-03 With Fiber1.10E-029.29E-038.30E-039.46E-03PPPVACellSteel B Figure 5-20. Absorption rate for Class V concrete with/without fiber. A) Initial absorption rate. B) Secondary absorption rate. 107

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0.000.010.020.030.04Absorption Rate (mm/s0.5) Initial Secondary Initial2.45E-022.54E-021.77E-022.39E-021.94E-02 Secondary1.45E-021.81E-021.26E-021.65E-021.39E-02PCPPPVACellSteel Figure 5-21. Absorption rate for Class II concrete 0.010.020.04sortionte (m/s5) 0.00 0.03Abp Ram0. Initial Secondary Initial1.72E-022.03E-021.35E-021.38E-021.55E-02 Secondary9.60E-031.10E-029.29E-038.30E-039.46E-03 PCPPPVACellSteel Figure 5-22. Absorption rate for Class V concrete 108

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5.3.5 Bulk Diffusion Test Results The coefficients of chloride diffusion on hardened concrete at 365 days were examined.Test results are summarized as follows: Figure 5-23 and 5-24 show typical examples of the chloride concentration profiles in mixture containing fibers had lower rates of the chloride diffusion when compared to Classes were observed beyond the first layer. The hooked-end steel fiber exhibited the coefficients by using Cranks solution to Ficks second law. Figure 5-25 shows the increased the coefficient of chloride diffusion for concrete Class II. The PVA fibers concrete pounds per cubic yard for Class II and V concrete. This figure illustrates that concrete concrete without fiber. Considerable reductions of chloride concentration for both concrete lowest chloride content in the fiber composite. Test results for the bulk diffusion were analyzed to get the best fit curve for the chloride coefficients of chloride diffusion for each fiber type. The addition of PP fibers slightly decreased the coefficient of chloride diffusion for Class II concrete, but not for Class V The use of cellulose fiber showed no effect on Class II concrete, but significantly increased the coefficient of chloride diffusion for Class V concrete. The steel fibers exhibited the greatest reduction of chloride diffusion for both concrete Classes. fficient and had a positive effect on resistance to chloride diffusion in concrete. Among the fiber types, steel fibers had the greatest resistance to chloride diffusion through the pore structure. Generally, the addition of PVA and steel fibers reduced the chloride coe 0510152025303540455000.511.522.533.54Mid-layer Depth from Surface (in)Cl Content (lb/yd3) PC-II PP-II PVA-II Cell-II Steel-II Figure 5-23. Chloride concentration for Classes II concrete 109

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0 50 500.511.522.533.54 10 15253040l Contentlb/yd) 203545Mid-layer Depth from Surface (in)C (3 PC -V PP-V PVA-V Cell-V Steel-V Figure 5-24. Chloride concentration for Classes II/V concrete 0510Diffusion Coefficien 15t 2025 (x10-12 m2/sec) Concrete Class II Concrete Class V Concrete Class II16.83 17.57 11.80 16.07 6.26 PCPPPVACellSteel Concrete Class V7.76 6.33 6.99 11.59 5.59 Figure 5-25. Coefficient of chloride diffusion for Classes II/V concrete 110

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5.4 Mechanical Property Test Results An experimental program was performed to examine the effects of fiber and fiber type on mechanical properties of hardened concrete. Compression, splitting tension, and pressure tensile concrete. A comprehensive summary of test results can be found in the appendix G. A more succinct summary of findings is presented in the following section. 5.4.1 Compressive Strength Test Results The experimental investigation for compressive strength tests is shown in Figure 5-26. The addition of PVA and steel fibers showed a small increase in the compressive strength for both concrete Classes. As expected, the addition of fibers did not affect peak strength. 5.4.2 Splitting Tensile Strength Test Results The splitting tensile test results for fiber and fiber type are shown in Figure 5-27. The addition of steel fibers showed a slight effect on the improvement of tensile strength for both concrete Classes. 5.4.3 Pressure Tension Test Results The experimental test results for pressure tension test are shown in Figure 5-28. Although the pressure tension test results have a similar trend in comparison with the splitting tensile strength test results, the reduction in strength of fiber mixes compared to plain concrete from er than for splitting tensile approach. However, these effects are almost certainly a result of the difference in specimen preparation. Plain concrete specimens were cast in cylinders, while FRC specimens were cored from slabs. The smoother, less permeable surface of the cast specimens required greater external pressure to achieve the same internal pressure as in the more open cored surfaces. This was the primary reason for the apparent difference in strength. strength testing results were used to evaluate physical and mechanical properties of hardened pressurized gas was great 111

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02468101214Compressive Strength (ksi) Concrete Class II8.208.098.417.709.26 Concrete Class V9.669 .95 10.329.8610.19PCPPPVACellSteel Fitrength for Classes II/V concrete gure 5-26. Compressive s 0 100200400itti Te 3005007001000Splngnsti) 600800900ile Strengh (ps Concrete Class II722 654 658 667 785 Concrete Class V781 652 649 722 809 PCPPPVACellSteel Figure 5-27. Splitting tensile strength for Classes II/V concrete 112

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100400Purn Stngs 3005006007008009001000e Tensioreth (pi) 200ress 0 Conc5 38 3 rete Class II83 7 73 620 776 Conc9 36 6 PCPA rete Class V92 7 77 598 803 P PV Cell Steel Pressur Clas II/V cote Bar Crosion T Resulis section sufor C the steel bar corrosion test. Corrosion in the Class V concrete and one PVA fiber specimen for Class II but continue to be monitored. The ion potential ofr and ctotal of 693 days (25 cycles) for PC, PP, PVA, and cellulose fibers, andal 617 (22 or steel fibe valuesd photophs of the effects of fiber and fiber l corrosio Appdix H. Test results forof ste corrosiond totaosion ahown i-29 and 5-3 of PVfiber aps to beesist mtranspof s into cohe haned cemt paste x showrelativehigh resistivity in terms of both time to initiation and corrosion rate from cyclic wetting and Figure 5-28 e tension strength for ses ncre 5.5 Steel or est ts Th mmarizes the results lass II concrete obtained from concrete has not been detected as of publication of this report corros the titanium ba urre nt as a function of tim e had been recorded for a mixe a tot days cycles) f r mix. Details on the an gra type on stee n can be found in the en time at the initiation el n a l corr re s n Figures 5 0. Only the addition A pear tter r ass rt o chloride ion ncrete. PVA fiber in t rde en matri ed ly 113

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dryinteel bar, which bers to the steel bar, thereby accelerating the corrosion rate fe, g. The addition of steel fiber, which showed the greatest resistance to mass transport of deleterious materials, showed the earliest failure time and relatively high corrosion rate. This result may have been caused by localized steel fiber corrosion near the s transferred higher current from the steel fi rom cyclic wetting and drying. PP fiber showed relatively good resistance to initiation timbut high corrosion rate after initiation of steel bar corrosion. PP fiber, which is relatively low modulus and tensile strength, does not resist stresses occurring from an increase in volume ofsteel bar. On the other hand, cellulose fiber mix showed relatively similar results in both initiation time and corrosion rate in comparison with plain concrete mix, implying fiber ballingin the matrix. 0100200300400 500iaito 600900Tnitny 7008001000 (da) ine to I Co ncrete Class II609PVAell 190.5 315 197 137 PC PP C Steel ure 5-29mes for initiation l corrosion for Class II concrete Fig Total ti of stee 114

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6000 01000300040003090150210270330390450510570630690Ttal Crrosn (C 20005000Time (days)ooio) PC PP PVA Cellulose Steel g tructive (Ultrasonic Pulse eable pore space change, carbonation depth, and EDS sults are tthVisual and Photographic Inspection e asurfaas geneuite simetween c and fibccontrol and fiber specimThe folg ationt wam sens exp to salt water immersionbited a erhed ides of the beam surSurface r for steersor sater imm (Figure ). Figure 5-30. Total corrosion rate for Class II concrete 5.6 Evaluation of Beams Exposed to Conditioning Determination of FRC beam specimens exposed to 27 months environmental conditioninwere evaluated using visual or photographic inspection, non-des Velocity) and destructive beam testing, perm SEM/ analysis. Re presented in he sections at follow. 5.6.1 Th ppearance of beam ces w rally q ilar b ontrol er specimens. Figure 5-31 shows surface appearan e for ens. lowin observ s were made: Sallay ater immersion: be pecim osed exhi thin of salt crystals attac to the s face. usting el fib was not observed f lt wa ersion 5-31d 115

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Swamp water immersion: swamp water conditioning with acidic solution showed severe degradation of beam surface for each mix. Acetic acid solutions containing vinegar lution of the components for the cement paste, aggregate (limestone), fibers and hydration products of cement paste. The surface of fiber specimens (PP, PVA, and steel fiber mixes) sliced from the slabs showed more distinct surface degradation, specifically limestone, due to its direct contact with acetic acid. Salt water W/D: beam specimens subjected to salt water wetting and drying cycles resulted in spalling failure on the surface of the specimens. Dissolved salt ions during wetting periods migrated into the concrete and then crystallized inside of the concrete near the surface as the water evaporated. As the salt crystals expanded, shear stresses accumulated, which resulted in spalling from the concrete surface (Kropp et al., 1995). The finished surface of the control concrete mix was covered by a dense cement paste. Sliced surfaces exposed aggregate or fiber showed and exhibited more pronounced spalling failure. The severe corrosion of steel fibers on the surface was only observed for salt water cyclic wetting and drying and swamp water solutions (Figure 5-31d). Specimens pre-cracked before saltwater conditioning re-adhered or healed due to dissolved materials (salt or lime) in solutions and sometimes cracks were initiated away from the pre-cracked plane resulting from conventional flexural beam testing. attacked the concrete surface and resulted in degradation or disso A gradarisor typcream) P) StibeLime water Immersion Salt water Immersion Swamp water Immersion Lime water Wet/Dry Salt water Wet/Dry Figure 5-31. Surface des. C) PVA fiber beam tion c ompa ons f fiber e. A ) Plai n Con ete b s. B P fiber beam s. D eel f r bea ms. 116

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B C Lime water Immersion Salt water Immersion Swamp water Immersion Lime water Wet/Dry Salt water Wet/Dry Figure water mersion SaImsSp wImsioLWlt w et/Dr Lim Im alt w ter mer ion wam ater mer n ime water Sa et/D ry ater W y e 5-31. Continued 117

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118 D Figure 5-31. Continued 5.6.2 Ultrasonic Pulse Velocity Inspection Ultrasonic Pulse Velocity tests, which are nondestructive, were performed before flexural beam testing to quantitatively evaluate the degree of degradation of FRC resulting from environmental conditioning. Percent changes in UPV compared with lime water immersion are shown in Tables 5-1 and 5-2. Detailed values of test results can be found in the Appendix I (Tables I-1 and I-2). Only swamp water immersion resulted in significant reduction in UPV for all fiber types and for both concrete Classes. As a result of relatively fast process of dissolution of limestone or fibers in acetic acid solutions, degraded volume and degree of degradation in beam specimens e of specimens density during exposure periods and relatively fast degradation process resulted in slower pulse wave velocities and the reduction was more for swamp water conditioning. Lime water Salt water Swamp water Lime water Salt water Immersion Immersion Immersion Wet/Dry Wet/Dry was larger or worse than in specimens submerged in salt water. Both effects from an increas

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Wetting and drying conditioning resulted in slightly lower pulse velocity for FRC mixes compared to control mixes. However, there was no difference between lime water w/d and salt water w/d conditioning. It appears that the effect of salt crystallization or spalling from repeated wetting and drying only affected the outer surface of the beam and did not affect a large internal portion of the beam. It is noted that the effect from cyclic wetting and drying definitely created a non-uniformly damaged beam specimen. Table 5-1. Percent change in UPV test results for Class II concrete Percent Change (%) UPV Environmental Exposure Lime-imm. Salt-imm. Swamp-imm. Lime-w/d Salt-w/d PP-II-Pre-cracked -6 -25 -4 -7 PP-II-Un-cracked -5 -25 -4 -7 PVA-II-Pre-cracked -6 -24 -5 -9 PVA-II-Un-cracked -5 -23 -5 -7 ASTM C 1399 Steel-II-Un-cracked -6 -20 -6 -6 PC-II-Un-cracked -5 -22 -6 -9 Steel-II-Pre-cracked -4 -19 -5 -5 Specimens PP-II-Un-cracked -6 -25 -4 -6 -8 ASTM C 1609 -6 PVA-II-Un-cracked -5 -21 -5 Specimens Steel-II-Un-cracked -5 -18 -5 Table 5-2. Averaged UPV test results for Class V concrete Percent Change (%) UPV Environmental Exposure Lime-imm. Salt-imm. Swamp-con Lime-w/d Salt-w/d PP-V-Pre-cracked -2 -18 -1 0 PP-V-Un-cracked -5 -20 -5 -3 PVA-V-Pre-cracked -7 -21 -5 -5 PVA-V-Un-cracked -5 -22 -4 -4 Steel-V-Pre-cracked -7 -17 -9 -8 ASTM C 1399 Specimens Steel-V-Un-cracked -7 -12 -9 -8 PC-V-Un-cracked -1 -13 2 4 PP-V-Un-cracked -6 -16 -3 -2 PVA-V-Un-cracked -6 -23 -3 -4 ASTM C 1609 Specimens -4 Steel-V-Un-cracked -6 -14 -5 119

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There was no difference in pulse velocity between pre-cracked beam and un-cracked beam. It appears that the dissolved salt or lime in solutions was attached to cracked surface and blocked penetration of deleterious materials into concrete along the crack path. 5.6.3 Permeable Pore Space Change Permeable pore space of tested beam specimens was determined at different times using the test method specified in ASTM C 642 to observe the change of voids resulting from ingress of chemical ions into concrete and associated chemical reactions. Permeable pore space was compared ed test results are shown in immersion and wet/dry showed more pronounced reducoids um, t to initial values measured before conditioning. Averag Table 5-3. Salt water conditioning for both tion in permeable pores in comparison with lime water conditioning. The change in vwas caused by the intrusion and chemical reaction ions (chloride, sodium, sulfate, magnesicalcium, potassium) into pore spaces. High concentration of NaCl solution effected the greatesreduction in pore space as a result of salt crystallization, while additional reduction in pore spacewas caused by other ions binding in the pore system. Table 5-3. Averaged permeable pore space before/after conditioning for Classes II/V concrete Permeable Pore Space (%) Concrete Environmental Exposure Before Exposure Limewater ImmersionSaltwater ImmersionLimewater W/D SaltwateW/D Class r PC-II 12.97 12.34 10.55 12.05 8.83 PP-II 14.26 13.37 11.12 13.14 11.PVA-II 13.55 13.32 11.37 13.24 12.56 II Steel-II 12.12 12.48 10.30 12.26 10.79 PC-V 12.19 10.60 9.11 10.68 93 8.44 PP-V 12.77 11.46 9.85 11.88 9.16 .20 14 PVA-V 13.60 12.35 10.00 11.76 10V Steel-V 13.04 12.06 9.90 11.82 9. 120

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5.6.4 Average Residual Strength (ARS) Test Resu lts r also presented in Appendix I (Figures I-1 to I-6). minimeach nd Class V concrete, respectively. PP and PVA fibers had similar averaged residual strength, which was s un-cracksalt c chemical typesresidual TableMix Immersion Immersion ampwater Immersion Limewater W/D Saltwater W/D This section summarizes residual strength test results for beams subjected to different environmental conditioning for 27 months. Detailed test results for individual beams can be found in Appendix I (Tables I-3 to I-8). Typical examples of residual load-deflection curves foeach fiber type and conditioning method are Three beam test results from five tested beams were averaged after removing maximum and um test results. Test results are summarized in Table 5-4. Averaged residual strength for conditioning method and fiber type are presented in Figures 5-32 and 5-33 for Class II a ignificantly lower than that of steel fibers. ARS was about the same for pre-cracked anded beams, indicating that pre-cracking did not accelerate fiber degradation. Formation of rystals in the pre-cracked area prevented further penetration of mass transport of ions. Acidic solutions resulted in significant reduction of averaged residual strength for all fiber because of limestones susceptibility to acetic acid. Similar trends of averaged strength were observed for both Class II and Class V concrete. 5-4. Averaged ARS (psi) test results Specimen Limewater Saltwater Sw Type Type Precracked bea ms 311 284 131 273 248 PP-II 8 8 PVA-II 7 Steel-II 32 Uncracked beams 248 210 148 331 23Precracked beams 362 277 107 422 38Uncracked beams 395 323 118 263 31Precracked beams 769 760 342 671 518 Uncracked beams 674 679 381 613 7Precracked beams 347 411 164 200 358 PP-V 10 Steel-V Uncracked beams 827 806 561 681 588 Uncracked beams 251 385 167 239 3Precracked beams 322 343 228 342 358 PVA-V Uncracked beams 266 328 186 334 328Precracked beams 847 785 374 665 636 121

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0Lime-imm.Salt-imm.Swamp-imm.Lime-WDSalt-WD 300600e Re 9001200(psi) 1500 Averagsidual Strength PP-II-Precracked PP-II-U ncracked PVA-II-Precracked PVA-II-Uncracked Steel -II-Precracked Steel-II-Uncracked Figure 5-32. Average residual strength results for Classes II concrete 030060090012001500Lime-imm.Salt-imm.Swamp-imm.Lime-WDSalt-WDAverage Residual Strength (psi) PP-V-Precracked PP-V-Uncracked PVA-V-Precracked PVA-V-Uncracked Steel-V-Precracked Steel-II-Uncracked Figure 5-33. Average residual strength results for Class V concrete 122

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5.6.5 Flexural Performance Test Results This section summarizes flexural performance test results for degraded beams subjected to different environmental conditioning for 27 months. Detailed test results for individual beams can be found in Appendix I (Tables I-9 to I-14). Typical examples for residual load-deflection curves for each fiber type and conditioning method are also presented in Appendix I (Figures I-7 to I-11). Three beam test results from five tested beams were averaged after removing maximum and minimum test results. Test results are summarized in Table 5-5. Table 5-5. Averaged test resu Class II concrete Class V concrete lts of flexural performance PP f11fp2 f6003 f1504 T1505f11fp2 f6003 f1504 T1505 Limewater Immersion 962 962 376 393 195 1079 1079 301 304 177 Saltwater Immersion 906 906 231 243 143 1277 1277 300 302 210 Swampwater Immersion 358 358 141 160 74 495 495 160 203 94 Limewater W/D 935 935 237 257 147 1189 1189 399 395 210 Saltwater W/D 967 967 339 364 179 1247 1247 x 306 203 PVA f11fp2 f6003 f1504 T1505f11fp2 f6003 f1504 T1505 Limewater Immersion 915 915 387 260 192 972 972 213 164 150 Saltwater Immersion 964 964 390 225 184 1272 1272 315 233 211 Swampwater Immersion 403 403 159 176 89 457 457 198 218 111 Limewater W/D 053 1053 324 293 181 1249 124397 220 193 Saltwater W/D 105 1105 329 218 181 1360 13606 285 221 Steel 04 T1505 9 40 f 1 1 f p 2 f 600 3 f 150 4 T 150 5 f 1 1 f p 2 f 600 3 f 15 Limewater Immersion 092 1124 1002 589 363 1143 1149 981 681 392 Saltwater Immersion 061 1061 731 414 274 1319 1319 998 641 385 Swampwater Immersion 477 477 448 376 175 589 589 493 434 205 Limewater W/D 114 1114 806 361 274 1245 1245 801 249 248 Saltwater W/D 234 1234 870 416 298 1282 1377 1272 545 419 f11 is first peak strength, psi. fp2 is peak strength after cracking, psi. f6003 is residual strength at net deflection of span/600, psi. f1504 is residual strength at net deflection of span/150, psi. T1505 is area under the load vs. net deflection curve to 0 to span/150, lb-in. Figures 5-34 through 5-39 show the percent change of several flexural performance measurements for specimens subjected to different conditioning methodselative to control specimens i, r mmersed in lime water for PP, PVA, and steel fibers, respectively. Once again 123

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because of limestones susceptibility to acetic acid, large reductions in all performance measurements were generally observed for specimens immersed in swamp water. Salt water immersion reduced residual strength and toughness of PP and steel fiber specimens in Class II concrete, where a smaller or no reduction was observed for the PVA specimens. Conversely, for Class V concrete salt water immersion resulted in 30-40% increase in performance measurements for PVA fiber specimens and more modest improvements for PP and steel fiber specimens. However, test results may not be reliable as expected in section 5.7. 5.6.6 Carbonation Figure 5-36 shows the dam/D and swamp water immersion. The damaged area for specimens exposed to salt water cyclic wetting and drying is shown in Figure 5-36a. Carbonation was only observed for swamp water conditioning in Figure 5-36b. Swamp water immersion with pH 4.5 appeared to have a severe extent of damage and carbonation on the fracture surface each of the fiber types and mixtures. It can be noted that fiber type for both concrete Classes had no effect on the resistance to carbonation as a result of the overwhelming effect of reaction with acidic solutions. aged and undamaged area for both salt water W -100-80-60-40-20020406080100Lime-imm.Salt-imm.Swamp-imm.Lime-W/DSalt-W/DChange of Flexural Performance (%) First peak strength Peak strength Residual strength at L/600 Residual strength at L/150 Toughness at L/150 Figure 5-3 4. Flexural performance comparisons for PP fiber mixes for Class II concrete 124

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-100-80-60-40-20020406080 100 Lime-imm.Salt-imm.Swamp-imm.Lime-W/DSalt-W/DChange of Flexural Performance (%) First peak strength Peak strength Residual strength at L/600 Resi dual strength at L/150 Toughness at L/150 Figure 5-35. Flexural performance comparisons for PP fiber mixes for Class V concrete -100-80-60-40-20020406080100Lime-imm.Salt-imm.Swamp-imm.Lime-W/DSalt-W/DChange of Flexural Performance (%) First peak strength Peak strength Residual strength at L/600 Residual strength at L/150 Toughness at L/150 Figure 5-36. Flexural performance comparisons for PVA fiber mixes for Class II concrete 125

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-100-80-60-40-20020406080 100 Lime-imm.Salt-imm.Swamp-imm.Lime-W/DSalt-W/DChange of Flexural Performance (%) First peak strength Peak strength Residual strength at L/600 Residual strength at L/150 Toug hness at L/150 Figure 5-37. Flexural performance comparisons for PVA fiber mixes for Class V concrete -100-80-60-40-20020406080100Lime-imm.Salt-imm.Swamp-imm.Lime-W/DSalt-W/DChange of Flexural Performance (%) First peak strength Peak strength Residual strength at L/600 Residual strength at L/150 Toughness at L/150 Figure 5-38. Flexural performance comparisons for Steel fiber mixes for Class II concrete 126

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-100-80-60-40-200204060 80ce ( 100Lime-imm.Salt-imm.Swamp-imm.Lime-W/DSalt-W/DChange of Flexural Performan%) First peak strength Peak strength Residual strength at L/600 Residual strength at L/150 Toughness at L/150 Figure 5-39. Flexural performance comparisons for Steel fiber mixes for Class V concrete A B Figure 5-40. Degraded area and carbonated depth on fracture surface for swamp water immersion. A) Damaged area. B) Carbonated depth. 5.6.7 Scanning Electron Microscopy Semi-quantitative chemical analysis for Scanning Electron Microscopy (SEM) with Energy Dispersive Spectrometer (EDS) were performed on fibers and beam specimens to observe microstructure changes in fiber surface and interfacial zone between the fiber and the matrix as a result of chemical reaction during environmental exposure. Two specimens for each fiber type, including limewater and saltwater immersion for Class II concrete, were chosen and analyzed. Specimens were sliced from the fractured beams, which were in a saturated condition 127

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due to long term exposure. Small unpolished specimens were then obtained using a diamond blade saw. This method was employed because the epoxy-impregnated saw polishing approach, generally used in sample preparation for concrete, can cause damage in the form of cracking patterns or crystals (Stella, 1995). Before examination, specimens were coated with a thin carbon film by sputtering using a low deposition rate. Secondary Election (SE) images, which are capable of displaying the morphology of the microstructure, were obtained as well as X-ray element analysis providing elemental compositions. Results are presented on a chart, where selected elements are recognized on a continuous spectrum according to the position of their peaks. Finally, a dot map indicating the distribution of a particular element was created. 5.6.7.1 Fibers subjected to salt and acidic solutions The results were used to study the nature of PP, PVA, cellulose, and steel fibers, as well as to evaluate the resistance to salt and swamp water solutions. Higher SEM magnification of fibers exposed to saltwater with 5% chloride and swamp water with pH 4.5 solutions directly for 45 The surface of the undamaged PP fiber was smooth and had long striations through the fibers but at high magnification (1000 ), the image showed fracture planes in the fiber (Figure 5-41a). Many fracture planes in the fiber were created by salt water reaction, where the salt crystals caused expansion of the fibers (Figure 5-41b). On the other hand, the smooth surface of PP fibers was transformed to a wrinkled shape and some thin fibrils appeared due to acidic attack (Figure 5-41c). The high magnification (1000 ) image of the surface of undamaged PVA fiber indicated the presence of many small split gaps, which provide a larger surface area, potentially improving the bonding of the fiber with cement paste (Figure 5-42a). However, the split gaps were filled with salt crystals, which caused expansion within the fibers, and a small amount of degradation was also found (Figure 5-42b). The sponge surface of PVA fibers indicated a little degradation from exposure to acidic solution. (Figure 5-42c). Numerous bunches of micro-fibers were packed for the original surface of cellulose fiber that were inter-twined (Figure 5-43a). An abundance of salt crystals were deposited (Figure 5-43b) and degradation was found on the fiber surface (Figure 5-43c). days showed the following characteristics: 128

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The surface of the original steel fiber was uneven, providing greater surface area that might have the potential effect of improving the bonding with cement paste (Figure 5-44a). A severe extent of rusting and iron was found on the surface of the fiber in both salt water and swamp water solutions (Figures 5-44b and 5-44c). 5.6.7.2 Degraded beam It was very difficult to detect property changes or reaction products from the chemical reaction with seawater solutions due to the limitations of the SEM/EDS analysis, which are qualitative in nature. Another reason for difficulty to discern the nature of the deterioration mechanism of fibers was that SEM analysis required very small, completely dry specimen, which tended to induce cracking or damage of the microstructure. In addition, sputter coating was required to induce conductivity. The properties of PP, PVA and steel fibers in the hardened cement paste matrix are summarized as follows: The SE image for PP fiber exposed to lime water immersion is shown in Figure 5-45a and X-ray spectrum for the whole area shown in Figure 5-45e indicated several kinds of peak elements (C, Ca, Mg, Si, Al, S, Fe, O). The dot map presented in Figure 5-45c shows distributions of peak elements using white dots. Distributions of carbon (C) and silica (Si) hydrate calcium hydroxide (CaOH2), C-S-H, and ettringite. Although different in SEM images between control and saltwater immersion for PP fibers was not clear in Figures 5-45a and 5-45b, tot map study in Figures 5-45c and 5-45d and X-ray element analysis in Figures 5-45e and 5-45f showed more pronounced changes as a result of degradation of specimen to salt water solution. Sodium (Na), magnesium (Mg), chloride (Cl), potassium (K) and sulfate (S) contained in salt water were detected. The test results of SEM and X-ray elemental analysis for PVA and steel fibers shown in Figures 5-46 and 5-47 showed similar characteristics in comparison with those of PP fibers. represent PP fibers and lime stone (coarse aggregate) respectively. Calcium (Ca) indicates d cement paste such as he d 129

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A Undamaged PP fibers: a) 100x, b) 1000x B Damaged PP fibers in saltwater solution (45 days): a) 70x, b) 1000x C Damaged PP fibers in swamp water solution (45 days): a) 700x, b) 1000x Figure 5-41. Surface properties of PP fibers 130

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A Undamaged PVA fibers: a) 150x, b) 1000x B Damaged PVA fibers in saltwater solution (45 days): a) 150x, b) 1000x C Damaged PVA fibers in swamp water solution (45 days): a) 180x, b) 1000x Figure 5-42. Surface properties of PVA fibers 131

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A Undamaged Cellulose fibers: a) 35x, b) 1000x B Damaged Cellulose fibers in saltwater solution (45 days): a) 35x, b) 1000x C Damaged Cellulose fibers in swamp water solution: a) 500x, b) 1000x Figure 5-43. Surface properties of cellulose fibers 132

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A Undamaged steel fibers: a) 450x, b) 1000x B Damaged steel fibers in saltwater solution (45 days): a) 100x, b) 1000x C Damaged steel fibers in swamp water solution (45 days): a) 90x, b) 1000x Figure 5-44. Surface properties of steel fibers 133

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A B Figure 5-45. PP fiber comparisons in limewater and saltwater immersion. A) SE image (60x) for limewater immersion. B) SE image (60x) for saltwater immersion. 134

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C D Figure 5-45. Continued. C) Dot mapping for limewater immersion. D) Dot mapping for saltwater immersion. 135

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E F Figure 5-45. Continued. E) EDS Spectrum for limewater immersion. F) EDS Spectrum for saltwater immersion. 136

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A B Figure 5-46. PVA fiber comparisons in limewater and saltwater immersion. A) SE image (60x) for limewater immersion. B) SE image (60x) for saltwater immersion. 137

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C D ) Dot mapping for Figure 5-46. Continued. C) Dot mapping for limewater immersion. Dsaltwater immersion 138

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E F Figure 5-46. Continued. E) EDS spectrum for limewater immersion. F) EDS spectrum for saltwater immersion. 139

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A B Figure 5-47. Steel fiber comparisons in limewater and saltwater immersion. A) SE image (60x) for limewater immersion. B) SE image (60x) for saltwater immersion. 140

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C D e 5-47. Continued. C) Dot mapping for limewater immersion. D) Dot mapping for saltwater immersion. Figur 141

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E F Figure 5-47. Continued. E) EDS spectrum for limewater immersion. F) EDS spectrum for saltwater immersion. 142

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5.6.8 Distribution Problem for CelluloBuckeye UltraFiber500 is 100% virgin specialty cellulose fiber designed to provide an improved level of secondary reinforcement with high fiber surface area, close fiber spacing, excellent bonding with the cement matrix, high tensile strength, as well as to improve concrete durability by reducing the transport of deleterious materials. The manufacturer indicates that the addition of UltraFiber500TM reinforcing fibers at a normal dosage rate in the form of 5 x 6 mm chips containing over 33,000 fibers does not require any mix design changes. They also indicate that fibers disperse best when added at the beginning of the batching sequence following normal mixing time and speed, as recommended by ASTM C 94 (Buckeye Technologies Inc.). However, cellulose fibers did not disperse properly in this project, and fiber balling was observed in the mixes. Test results for mechanical properties (compression, splitting tension, pressure tension strength) showed no improvement in strength or transport properties (absorption, permeability, diffusion), clearly indicating no improvement in resistance to mass transport of deleterious materials into concrete. Therefore, the number of beams for degraded specimens was reduced to two specimens for each environmental condition. Beam test results showed no post-cracking behavior and undistributed fibers were found as shown in Figure 5-48. Figure 5-48. Cellulose fibers distribution: undistributed fibers (left) at this project; good distribution (right) in cement paste from manufacture se Fibers TM GGoooodd DDiissppeerrssiioonn BBuucckkeeyyee TTeecchhnnoollooggiieess IInncc.. 143

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5.7 Discussion of Conventional Beam Approach For fiber reinforced concrete, the flexural beam te st with third-point loading is most commonly used to evaluate the effect of fiber degradation on the flexural strength and toughness due to bridging effect subsequent to matrix cracking (Kosa et al., 1991). Previous researchers (Morse et al., 1977; Mangat et al., 1985) have used beams subjected to the wet/dry cycles to evaluate the durability of fiber reinforced concrete. To accelerate the deterioration mechanism, specimens were exposed to intermittent wetting and drying in simulated solutions over specific time periods. The durability performance of the specified beams representing structural elements such as columns or bridge decks was evaluated by determining the rate of reduction in strength or pullout resistance throughout the cracking process. Although the flexural beam test is easy to prepare and perform, its cross-sectional stress and strain distributions are non-uniform and crack initiates at the bottom of the specimen, sometimes outside the middle third of the span for third-point loading. Also, beam specimens ing system developed in this study, created y nn the beam cross-section and variab d iber subjected to salt water conditioning for 6 months with the new wet/dry condition highlon-uniform degradation i le crack initiation at failure as shown in Figure 5-49, making test data is difficult to interpret. Typical examples of load versus deflection curves for PP, PVA, and Steel fibers exposed to limewater solution for 27 months are shown in Figures 50, 5-51, and 5-52. Beam specimens foreach fiber type showed almost the same values in modulus of rupture due to uniformly distributed maximum moment at the bottom of the beam, and then the applied load droppesignificantly subsequent to matrix cracking, when matrix stresses were transferred to the fand the fiber-matrix interface. A schematic diagram for unstable failures in fiber reinforced concrete is presented in Figure 5-53. The instability at first cracking from non-uniform stress 144

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distribution in the cross-section and variable cracking away from the specimens center resulted in highly unstable behavior of fibers during the post-cracking process. A B C Figure 5-49. Test result for flexural beam testing with third-point loading. A) Multiple crackspecimen and stress distribution. ing for PVA fibers. B) Multiple cracking for Steel fibers. C) Non-uniformly damaged t c Damaged Zone Non-damaged Zone 145

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0100020003000400050006000 700080009000 0.000.020.040.060.080.100.120.140.160.180.20Deflection (mm)Load (lbf) PP-II-Limewater-Immersion-1 PP-II-Limewater-Immersion-2 PP-II-Limewater-Immersion-3 PP-II-Limewater-Immersion-4 Figure 5-50. PP fiber mix for limewater immersion for 27 months 0100020003000400050006000 9000 7000 80000.000.020.040.060.080.100.120.140.160.180.20Deflection (mm)Load (lbf) PVA-II-Limewater-Immersion-1 PVA-II-Limewater-Immersion-2 PVA-II-Limewater-Immersion-3 PVA-II-Limew ater-Immersion-4 PVA-II-Limewater-Immersion-5 Figure 5-51. PVA fiber mix for limewater immersion for 27 months 146

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0 100020003000 4000Loa 500060007000 (lbf) 8000 9000d ST-II-Limewater-Immersion-12 ST-II-Limewater-Immersion-13 ST-II-Limewater-Immersion-14 ST-II-Limewater-Immersion-15 0.000.020.040.060.080.100.120.140.160.180.20Deflection (in) for limewater immersion for 27 months Figure 5-53. Unstable failure in fiber-reinforced concrete Figure 5-52. Steel fiber mix O Load Net D e fl ect i o n A B C F D E Toughness (ASTM C 1609) = Area OABCF Overestimated To ughness = Area ABED Inst(high e ability subsequent tonerg anflecti Matrix Cracking y dissipation d rate of de on) 147

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Coefficients of variation fo r flexural performance test results are shown for each fiber type and c y m nt tion. Therefore, another approach is needed for specimen prepa onditioning method in Figures 5-54, 5-55, and 5-56. Significant increase in coefficient ofvariation was found subsequent to matrix cracking for all fiber types and conditioning methods. Non-uniform stress distributions in the cross-section, unstable crack initiation, and high energdissipation (overestimated toughness) at first cracking appeared to affect the failure mechanisof fibers during post-cracking. The effects of overestimated energy to toughness measuremefrom instability subsequent to matrix cracking are shown in Figure 5-57. It is noted that PP and PVA fibers were significantly affected. Consequently, the flexural test was found to have serious limitations for durability evalua ration, conditioning, and testing. 0102030 4050f Vaiatio (% Peak load Post-crackloadPost-crackdeflectionPeakstrengthResidualstrength atL/600Residualstrength atL/150Toughnessat L/150Coefficient orn) PP-II-Limewater-Immersion PP-II-Saltwater-Immersion PP-II-Limewater-WD PP-II-Saltwater-WD PP-II-Swampwater-Immersion Figure 5-54. Coefficients for PP fiber beams 148

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50 01020Coeficien 30riat 40Peak load Post-crackPost-crackPeakthResidualstrength atL/600Residualstrength atL/150Toughnessat L/150ft of Vai%) on ( PVA-II-Limewater-Immersion PVA-II-Saltwater-Immersion PVA-II-Limewater-WD PVA-II-Saltw ater-WD PVA-II-Swampwater-Imm loaddeflectionstreng ersion Figure 5-55. Coefficients for PVA fiber beams 10203050Coeficien of Vriatin (% 0 40Peak load Post-crackPost-crackPeakResidualL/600ResidualL/150Toughnessftao) Steel-II-Limewater-Immersion Steel-II-Saltwater-Immersion Steel-II-Limewater-WD Steel-II-Saltwater-WD Steel-II-Swampwater-Immersion loaddeflectionstrengthstrength atstrength atat L/150 Figure 5-56. Coefficients for steel fiber beams 149

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010 204050eresmatd Tohnes (% 30Lime-imm.Salt-imm.Lime-W/DSaltW/DSwamp-immPercentage of Ovtieugs) PP-II PVA-II Steel-II Figure 5-57. Overestimated energy effect on determination of toughness 5.8 Summary of Conventional Beam Testing This section summarizes the environmental resistance of FRC exposed to various conditioning methods based on test results fromperformance (ASTM C 1609). The results may be summarized as follows: Test results from both average residual strength (ASTM C 1399) and flexural performance (ASTM C 1609) tests were not effective to evaluate deterioration of FRC exposed to various conditions. Although specimens exposed to acidic solutions showed significant degradation in both ARS and flexural performance for all fiber types, conventional flexural beam approach having non-uniform stress and strain distribution through the cross-section, multiple cracks initiating at the bottom of the specimen, and instability subsequent to matrix cracking, affected the pull-out mechanism of fibers making it impossible to clearly assess fiber resistance to crack propagation. Observation and test methods from SEM and EDS analysis were probably also affected by problems associated with the flexural beam approach. Beam specimens also can be problematic in terms of achieving proper conditioning using s the outerged cross-sections. residual strength (ASTM C 1399) and flexural cyclic wetting and drying. It was found that cyclic wetting and drying only degrade half inch shell of beam, which results in non-uniformly dama 150

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These results clearly indicated the need tovelop effective conditioning to achieve uniformly damaged specimen. Also, proper test methods are required to clearly evaluate failure mechanisms from the pull-out of fibers as a result of chemical deterioration. de 151

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CHAPTER 6 DEVELOPMENT OF CONDITIONING AND TEST METHOD 6.1 Introduction A conditioning system that effectively accelerates damage and results in a uniformly damage specimen is required for proper evaluation of the effects of degradation on physical properties. Furthermore, an effective testing system that is sensitive to the effects of fibers is also needed to evaluate differences in fiber pull-out resistance caused by deterioration. Conceptually, uniform stress distribution at the failure surface can be obtained in the direct tension test. However, the test specimen must be perfectly glued to the loading heads or held between grips. Mechanical grips are generally a problem in direct tensile testing since a biaxial tensile stress conditions will be induced in the specimens end through the lateral confinement (Mier, 1997). A similar effect develops when lodeleteriouso the specimen and for obtaining a uniformly degraded cross-section, as well as uniform stress and strain distributions. 6.2 Determination of Conditioning and Specimen Thickness Figure 6-1 indicates that absorption depths by capillarity for different fiber types and concrete Classes clearly depend on time. A seven day wetting cycle is needed to penetrate Class II concrete by capillary action to a depth of one inch. Additional time is required to penetrate Class V concrete, which had less depth of penetration than Class II concrete at seven days. A 9.5-mm diameter hole was introduced at the center to concentrate stress and further accelerate ingress of deleterious materials around the hole. Based on absorption test results, a one inch thickness with the circular hole in the center of the specimen, obtained by seven days of wet ading heads are epoxied to the specimen, which is also time consuming. The indirect tensile test mode has unique advantages for transporting material int 152

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conditioning by capillary action from both sides, appears to be appropriate to obtain a uniformly damaged FRC specimen for the indirect tensile testing. 0.00.20.40.60.81.01.21.41.61.82.0Absorption Depth (in) PC-IIPP-IIPVA-IISteel-IIPC-VPP-VPVA-VSteel-V 6 hour 2 day 4 day 7 day Figure 6-1. Absorption depths vs. time for fiber type and Classes II/V concrete 6.3 Proposed Test Method The indirect tensile test has been developed and used extensively to determine stiffness and fracture properties of asphalt materials. A 3-dimensional finite element model with 100 mm diameter and variable thicknesses was used to evaluate and analyze indirect tension specimens (Roque et al., 1992). The theoretical stress distribution on the vertical diametral plane is fairly uniform near the center of the specimen as shown in Figure 6-2. However, there are significant differences between the theoretical plane stress analysis and the 3-dimensional specimen behavior. Uniformly distributed horizontal tensile stress was found to exist for specimen thickness of less than one inch. On the other hand, for specimen thickness of 2.5 inches and greater, the difference in horizontal stresses between the specimen face and center is about 30%. 1 inch depth at 7 day 153

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154In addition, non-uniform specimen bulging on the specimen face and edges occurs, which affects deflection measurements obtained at the surface by producing sensor rotating during the test. Therefore, one inch thickness is not only most appropriate for evaluating FRC with Indirect Tensile Test (IDT) based on the absorption test results, but also from the standpoint of stress uniformity. The sensor mounting system shown in Figure 6-2, having a gage length of one inch was recommended for 4 inches diameter specimens (Roque et al., 1992). A key advantage of IDT is that the fracture plane is known before testing. Therefore, fracture limits can be determined exactly on the fracture plane. Figure 6-2. Theoretical stress distribution and gage points spaced at depth/4 The schematic test setup for SuperpaveTM indirect tensile mode is shown in Figure 6-3. The one deviation from standard SuperpaveTM IDT testing is the use of a 100100 mm (4 4 inches) square shape specimen with 25.4 mm (one inch) thickness as opposed to a circular specimen. The rectangular specimens can be obtained more easily from beam specimens. Finite element analysis was performed to compare stress distributions between circular and square shapes. The results presented in Figure 6-4 show that the same stress distribution along vertical D/4

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plane was observed between the square and the circular specimen. As mention earlier, to accelerate transport mechanisms and concentrate stress, a 9.5 mm size circular hole as showFigure 6-5 was cored in the center of the sp n in ecimen. Figure 6-3. SuperpaveTM IDT specimen setup 0.00.51.01.52.02.5-6-5-4-3-2-1012Y-axis Tensile Stress Distribution (ksi)Vertical Distance (in) Circle IDT at Center Square IDT at Center Figure 6-4. 2-Dimensional FEM analysis for circle and square shapes IDT 155

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Figure 6-5. Proposed test specimen and stress distribution 6.4 Evaluation of Fiber Resistance to Conditioning 6.4.1 Experimental Program An experimental program was carried out to evaluate the resistance of fibers to crack propagation in concrete subjected to different conditioning methods. The experimental program included the following components: One months. Class II concrete for PP, PVA, and Steel fibers was used. Tests were not performed for control and cellulose fiber ms because they did not exhibit post-cracking behavior. Table 6-1 summarizes fiber type and number of specimens used for testing. Strength testing was performed at a constant rate of net displacement of 0.005 in/min until a crack was initiated in the specimen. (3) Repeated Load Testing Repeated load testing was performed after crack initiation with a constant repeated haversine load of 0.1 second followed by a rest period of 0.9 second. Two horizontal deformation measurements, applied load, and the corresponding time were recorded at a rate of 500 points per seconds for 6 seconds at intermittent times until the maximum horizontal deformation was reached. (1) Specimen Preparation inch IDT specimens were sliced from beam specimens conditioned in lime water at 21 (1) Specimen Preparation inch IDT specimens were sliced from beam specimens conditioned in lime water at 21 ixeixe (2) Strength Testing (2) Strength Testing 156 x, tension xy 156 Figure 6-5. Proposed test specimen and stress distribution 6.4 Evaluation of Fiber Resistance to Conditioning 6.4.1 Experimental Program An experimental program was carried out to evaluate the resistance of fibers to crack propagation in concrete subjected to different conditioning methods. The experimental program included the following components: One months. Class II concrete for PP, PVA, and Steel fibers was used. Tests were not performed for control and cellulose fiber ms because they did not exhibit post-cracking behavior. Table 6-1 summarizes fiber type and number of specimens used for testing. Strength testing was performed at a constant rate of net displacement of 0.005 in/min until a crack was initiated in the specimen. (3) Repeated Load Testing Repeated load testing was performed after crack initiation with a constant repeated haversine load of 0.1 second followed by a rest period of 0.9 second. Two horizontal deformation measurements, applied load, and the corresponding time were recorded at a rate of 500 points per seconds for 6 seconds at intermittent times until the maximum horizontal deformation was reached. x, tension xy Reality Theory

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Table 6-1. Number of specimens tested for IDT for Class II concrete Environmental Exposure Mix Type Fiber Type Fiber Volume Fraction Vf (%) Limewater Immersion Saltwater Immersion Limewater WD SaltwaterWD PP Polypropylene 0.5 3 3 3 3 PVA Polyvinyl Alcohol 0.75 3 3 3 3 Steel Hooked Steel 1.00 3 3 3 3 6.4.2 Exposure Conditions IDT specimens were exposed to limewater immersion, saltwater immersion, limewater W/D, and saltwater W/D for an additional 6 months. Water temperature and simulated seawater system proposed for beam conditioning with heater/blower was applied with a reduced tank volume. Seven days for wetting and seven days for drying time were repeated to maximize ental tal conditioning is summarized in Figure 6-6. 6.4.3 6-7. solutions were identical to those used for beam conditioning. The new wet/dry conditioning chemical ions gain and loss with minimal micro-damage. A flow chart showing the experim program and numbers of specimens for environmen Testing Procedures Indirect tensile test with low loading rate (0.005 in/min) was first carried out to initiate cracking in the hardened cement paste matrix. Slow loading rate of cross-head movement minimized the energy dissipation and the high rate of deflection of the specimen subsequent to first cracking. Once first cracking was initiated, repeated loading was performed for each fiber type using 90% of the averaged maximum load required to initiate cracking. Total horizontal deformation, resilient horizontal deformation, applied load and the corresponding times were measured. The test setup for IDT is shown in Figure 157

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Figure 6-6. Flow chart for experimental program Figure 6-7. Test setup for IDT 6.4.4 Evaluation of the Fracture Tests This section summarizes the fracture test results obtained from strength and repeated load tests for each fiber type after 6 months of accelerated environmental conditioning. Evaluation of the fracture test results presented in this section includes: (1) visual examination of fractured specimens; (2) strength test results; (3) evaluation of horizontal deformation; (4) evaluation of horizontal resilient deformation ratio. Mix t yp e S p ecimen condition Ex p osure condition Ex p osure time PP-II PVA-II Steel-II Limewater-Immersion Saltwater Immersion 4 x 4 x 1 in. with Hole in Center Limewater WD 40C 40C/7% Cl 40C 6 months Saltwater WD 40C/7% Cl 158

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6.4.4.1 Visual examination of fractured specimens Fracture subsequent to matrix cracking for each fiber type was exactly initiated at the center of the hole, which generated the maximum tensile stresses, as shown in Figure 6-8. Significant degradation of the matrix and the fiber on the surface for each fiber type was observed for cyclic wetting and drying in saltwater. Among fiber types, considerable steel fiber corrosion was found in both surface and internal specimens for salt water immersion and salt water cyclic wetting and drying as indicated in Figure 6-9, as well as that of the cored hole surface showing significant steel fiber rusting. It appeared that the new conditioning system from specially designed heater/blowers completely saturated IDT specimens and generated uniformly damaunifo6.4.4.comppaste ed the load fdeflecre. It was ninimize the instability embe ged specimens. In addition, the fractured planes subsequent to matrix cracking were rm regardless of fiber type. 2 Examination of strength test results Figures 6-10, 6-11, and 6-12 show strength test results with loading rate of 0.005 in/min ared with the flexural beam test results subsequent to crack initiation in the harden cement matrix. Indirect tensile mode for PP, PVA, and Steel fiber mixes instantly transferrrom the matrix to the fiber without the high energy dissipation and the high rate of tion, which was commonly observed in beam testing at the moment of matrix failuoted that strength tests performed at slower loading rates m subsequent to matrix cracking which can significantly affect post-cracking behavior of fibers dded in the hardened cement paste matrix. 159

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A B C Figure 6-8. Surface degradation and failure plane for saltwater cyclic W/D. A) PP fiber specimen. B) PVA fiber specimen. C) Steel fiber specimen. 160

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A B er ter immersion and w/d. Figure 6-9. Fractured surface degradation for Steel fibers. A) Comparison with lime watimmersion and w/d. B) Comparison with salt wa 161

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162 00.0000.0020.0040.0060.0080.0100.0120.0140.0160.0180.020Deflection (in) 5001000 1500Llbf) 2000oad ( 25003000 35004000 PP-II-Limewater-Immersion PP-II-Saltwater-Immersion PP-II-Limewater-WD PP-II-Saltwater-WD A 08000.0000.0020.0040.0060.0080.0100.0120.0140.0160.0180.020Deflection (in) (lbf) 1000200030004000Load 500060007000 09000 PP-II-Limewater-Im mersion PP-II-Saltwater-Immersion PP-II-Swampwater-Immersion PP-II-Limewater-WD PP-II-Saltwater-WD B Figure 6-10. Comparison of strength test results at first cracking for PP-II mixes. A) IDT. B) Beam test. Post-Loading Deflection Point Matrix Cracking Deflection Point Matrix Cracking Deflection Point Post-Loading Deflection Point

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163 05001000150020002500300035004000180.020 0.0000.0020.0040.0060.0080.0100.0120.0140.0160.0Deflection (in)Load (lbf) PVA-II-LimewaterImmersion P VA-II-Saltwater-Immersion PVA-II-Limewater-WD PVA-II-Saltwater-WD A 030000.0000.0020.0040.0060.0080.0100.0120.0140.0160.0180.020 100020009000Deflection (in)ad) 40005000600070008000Lo (lbf PVA-II-Limewater-Immersion PVA-II-Saltwater-Immersion PVA-II-Swampwater-Immersion PVA-II-Limewater-WD PVA-II-Saltwater-WD T. B) B Figure 6-11. Comparison of strength test results at first cracking for PVA-II mixes. A) IDBeam test. Matrix Cracking Deflection Point Post-Loading Deflection Point Matrix Cracking Deflection Point Post-Loading Deflection Point

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164 300035004000 05001000Deflection (in) 150020002500Load ( 0.0000.0020.0040.0060.0080.0100.0120.0140.0160.0180.020lbf) ST-II-Limewater-Immerison ST-II-Saltwater-Immersion ST-II-Limewater-WD ST-II-Saltwater-WD A 01000200030006000700080009000Deflection (in)ad (lf) 400050000.0000.0020.0040.0060.0080.0100.0120.0140.0160.0180.020Lob ST-II-Limewater-Immersion ST-II-Saltwater-Immersion ST-II-Swampwater-Immersion ST-II-Limewater-WD ST-II-Saltwater-WD B Figure 6-12. Comparison of strength test results at first cracking for steel-II mixes. A) IDT. B) Beam test. Matr Post-Loading Deflection Point ix Cracking Deflection Point Matrix Cracking Deflection Point Post-Loading Deflection Point

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6.4.4. and t fibers stribution of stresses around the fracture plane resulting from slow 6-13b n be 3 Examination of repeated load test results Bridging forces from the hardened cement paste matrix to the fiber resulting from shear deformation at the fiber-matrix interface can be represented as fiber resistance to crack propagation or pullout from the matrix during post-cracking behavior. The mechanical bondingproperties for degraded fibers at the interface govern the fracture toughness and durability of FRC and results in different fracture mechanisms during crack propagation (Beaudoin, 1990 Bentur and Mindess, 1990). Typical test results from repeated load testing in Figure 6-13a show that the matrix and thefiber simultaneously resist crack propagation and/or pull-out of fibers embedded in the matrix during the initial part of cyclic loading. The reason for this initial cracking behavior is thain concrete immediately resist a crack propagation of the matrix subsequent to first cracking dueto the effect of fairly uniform di loading rate. Therefore, the instant when fiber resistance initiates and matrix effect is minimized, needs to be clearly identified. Horizontal deformations were averaged from six repeated cycles as shown in Figure and were plotted again in Figures 6-14, 6-15, and 6-16 for each fiber type. Averaged horizontal deformation clearly shows the effects of matrix and fiber on post-cracking behavior and caused to determine the point when the effect of the matrix minimizes. 165

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166 0.0.0.0050.0070.009300No. of Cycleseraged Hontal Drmatin) 000050100150200250 0.001002Av 0.0030.004rizo 0.006efo 0.008on (i 0.010 Steel-II-Saltwater Immersion Resilient Deforma tion A 0.00015115215315415515615715No. of Cycles 0.001Av 0.002ntal 0.003rma 0.004n) 0.005 8erage Horizo Defotion (i Steel-II-Saltwater Immersion Figuroncrete. A) Averaged horizontal deformation vs. number of cycles. B) Averaged horizontal deformation vs. number of cycles @150 cycles. Matrix/Fiber Zone Fiber Bridging Zone Horizontal Deforma tion 1 2 3 4 5 6 B e 6-13. Repeated loading test results for steel fiber mix for Class II c

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0.000 0.0160.020 0.004rage 0.008ntal 0.012efo 010020030040050060070080090010001100 120013001400No. of CyclesAved Horizo Drmation (in) ST-II-Limewater-Immersion ST-II-Saltwater-Immersion ST-II-Limewater-WD ST-II-Saltwater-WD Figurformation vs. number of cycles for steel fiber mix e 6-14. Averaged horizontal permanent de 0.000010020030040050060070 0.004 Ho 0.008tal D 0.0120.016080090010001100120013001400Averagedrizoneformon (in 0.020) PP-II-Limewater-Immersion PP-II-Saltwater-Immersion ati PP-II-Limewater-WD PP-II-Saltwater-W No. of Cycles D Figure 6-15. Averaged horizontal permanent deformation vs. number of cycles for PP fiber mix. 167

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0.0000.0040.0080.012 0.016on (in 0.02000300400500007008001000110012001300No. of CyesAveragorizol Deti) 10 200 6 900 1400 cl ed H nta forma PV A-II-Limewater-Immersion PVA-II-Saltwater-Immersion PmewaD VA-II-Li ter-W PValtw A-II-S ater-WD Figure 6-16. Averaged horizontal permanent deformation vs. number of cycles for PVA fiber mi6.4.4.4 Evalu ofre menisms oibersWecharatana and Shah (1983) proposed the idealization of crack subsequent to matrix cracking tin traction free zone, a fiber bridging zone, and a matrix process zone as fiber bridging zone showing crack closing ssure fromtionp of the fbers shoud be determined tvaluluanifibers degraded by environmental conditioning. The schematic diagram in Figure 6-17 describes lculation procedure for determination of the point where fibers stabilize crack propagation and the evaluation of effects of degradation of fibers from resilient deformation ratio can begin. ulation procedure involves the following steps: 1. Determine the point when the matrix effect minimizes and only fibers resist crack ropagatiowrack clooumber of load repetitions (N) in Figure 6-17a. Draw linear regression line 1 corresponding to matrix/fiber zone and lineagressione 2 cspondto fiber bridging zone. x ation failu cha f f Determination of Crack Stabilization of Fibers: as consis g of a shown in Figure 2.4. Among the three zones, the pre fric al sli i l o e ate fai re mech sms of the ca Calc pn on sh ing c sing pressure from the plot of horizontal def rmation ( ) vs. r re n li orre ing 168

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2. Determine point A, corresponding to the two regression lines intersect. Find point B (N starts. deformation ratio (H/Hing zone and plot the linear regression line 3 in iguredients degraded by conditioning represent rate of ffn and o evsist dein tracphase. Figure 6-17. Schematic diagram expng calcun prre for ret deforn rbridging zone Horizontal Deformation () B the point where B ), which is number of load repetitions to when the fiber bridging zone 3. Determine the resilient horizontal deformation ( H0 ) at point B (N B ). Plot the resilient 0 ) for fiber bridg from fiber and fiber type Fsti 6-17b. Graess reduction were used t aluate re ance to gradation he post-c king laini latio ocedu silien matio atio for fiber 1 Num ber of Re Load p licat ion ( N ) Linear Regression Line 1 ( Matrix/Fiber Brid g in g ear Rssion Line 2 Lin egre ( F iber Brid g in g Zone ) A Num ber of Load Re p licati on ( N ) Lin ear Rssion Lin egre e 3 ( Fiber Brid g in g Zone ) A B N B N B Resilient Deformation Ratio (/) Gradient H H0 B 169

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Results and Evaluation: Detailed test results fralysis for failure mfiber bridging zone can be f in Appenmm tesults to fibeg zfor each fiber type subjected to different conditiome-18, 6-19, and 6-20. Averaged rates of stiffness reduction, which are the gradients from the linear regression line for fiber bridging zone, are summarized in deterioration of fibers is summarizedllows: Limon of PVA and steel fibers to limewater immwed good resistto mech to PP Pand have relativelyh surfaces, highlus, and uy have bonding in the hardened cemete (steer wbest). Hor, PVAstfibers are much more susceptible to degrad whejected toater imion(PVA fiber was the worst). This is the reason why PVA and steel fibers in saltwater immowed much lowestance tck pation thaewater rsiOn the other hand, PP fibers have a naturally smootce, are hphobic urdo bonding in trdened nt pnd have odulusConsequently, PP fibers had the highest absoeable pore space among all er mixes. Thplies thass transport of deleus mateinconcrete with PP fibers is greater than that of PVA and steel fibersever, thdegradation process of PP fibers themselves, which have naturally strong resistance to acid, sal solutions, was mslower twat. Saltions in PP fibertributedres filled wt degrad offibers, which appeared to increase the density of PP fiber mix, thermprovimechanical properties. This is the reason w fi saltwatewed higresistance to crack propagation than PVA and steel fibers. LimSaltwater W/D: thetion of andfibers toater wclshowed good resistance to mecal degron cred to PPrs. PVAstefibtter bonding in trdened nt pand maintough rncemicro dand drying. For saltwater w/d cycles PVA fiber watly degraded anded lowtanrack proion. PVedegraded in saltwater solution and could not resist stresses resulting from salt cry in the interfaciae. This is the reason why steel fibers having high modulus relative to PVA fiber showed better recrystallization in pores. It is interesting to note that steel fibers expto saltw/cycles showed better resistanc those ed twater wcles. Threavolsteel corrosion osurfacearednsiderabntributeresistance of stresses from repeated shrinkage effect (micro-damage). The resistance of PP fibers to cyclic w/d in limewater was relatively weak compared to saltwater w/d because om linear regression an echanisms of fibers to ound dix J. Su arized t res r bridgin one ning thods are shown in Figures 6 Figure 6-21. Evaluation for as fo ewater/Saltwater Immersion: the additiersion sho ance anical degradation com pared fibers VA steel fibers roug modu suall good nt pas l fibe as the weve and eel ation n sub saltw mers ersion sh r resi o cra ropag n lim imme on. h surfa ydro in nat e, not have good he ha ceme aste, a low m rption rate and permt ma control and fib is im terio rials to How e t and alkalitwater solu uch s con in sal to po er than either PVA or steel fibersbeing ithou ation eby i ng hy PP bers in r sho her ewater/ addi PVA steel limew /d cy es chani adati ompa fibe and el ers have bemage induced by cyclic wetting a he ha ceme ste a ain en esista to s significan show resis ce to c pagat A fib r stallization l zon sistance to stresses as a result of salt osed ater w d e than expos o lime /d cy e inc sed ume from n the appe to co ly co to 170

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the effect of w/d condition in limewious chemical ions simply causes repeated stresses anore, PP fibers, which are not structural, could not resist the stresses from cyclic w/d. However, salt crystallization in ut which contrtress ater without var d micro-damage in the interfacial zone. Theref saltwater w/d cycles filled the relatively high pore content in the PP fiber mixes witho fiber dam age, ibuted to increased resistance to repeated s es. 0 1Re 2nt 3for 4on 5tio 60515504045500Nfles 0 100 0 200 2 0 300 35 0 0 o. o Cyc si lie De m ati Ra ST-ewr Immon Lim ate ersi ST-water Immersion Salt ST-ewr W/ Lim ate D ST-water W/D Salt -18. Resilient ronio cycles for fiber bridging zone (steel fibers) Figure 6 defo mati rat vs. n o. of 01234 6 5tio 0500005000350400450500N CyRnt Defotion Ra rma PVA-L imewater Immersion PValtw Immon A-S ater ersi P VAmew/D -Li ater W P VAltwa/D -Sa ter W esilie 10 150 2 2 3 o. of cles Figure 6-19. Resilient deformation ratio vs. no. ycler fibridg zoPP fi) of c s fo ber gin ne ( bers 171

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6 0 1340500500035404550Nf Cy Deformn Ratio PVA-Limewater Immersion PVA-S altwater Immersion P Vme W A -Li w ater /D P VAltwa/D -Sa ter W 5 atio 2esilient 10 150 200 2 3 0 0 0 0 o. o cles R Figure 6-20. Resilient deformation ratio vs. no of cycles for fiber bridging zone (PVA fibers) 0. 135600.10.02340.012200.5993.008.000.00.10.20.30.40.50.67ewrImmersionSateImmersionimeate/DSater W 0. 84 0 137 0.0 08 0 46 0.035 0 626 0.14 4 0.0007 0. Lim ate ltwa r L w r W altw /D R ate o f St iff nes s R e duc tio n PP Fiber Mix PV Fiber A Mix Steel Fiber Mix -21. Ratetsun lineares asiset deation ratio Figure 6 of s iffne s red ctio from regr sion naly of r silien form 172

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6.5 Summary of Findings Findings from this portion of the study m Moisture movement by cillaryion a mfaster transport mnismn that of permeation and diffusion processes through cote mix ais the effective to accele masnspof deriouate ane detratio. Absorption test was identifas tosticalechanism fetermng damage conditio method and specimeickn reqd toplem the rect tensile test mode. A 14-day wetting and drying cyclic conditioning procedure was rcular he cenr of thpecimmechanisms and concentrate stress around the hole. FEM analysis indicated the same s diutio cirr aquarapedmens subjected to indirect tension tehindallo for ing o.4 mm thick square specimens sliced from caeamslab The use of thin Ipecimhasque antaforspog deriousteria 100 mm square specimen with ah a hole cored at its center recommto moeffectly a thect oiber detratio FR Strength testing windirete significa reduced the high energy dissipn anh rof dctionseqt to hard cee cracking, w is a mooblessociated with the conventional flexural beam approach. Steel fiber mix had the strongest resistance to crack propagation in limewater imm atrix. PVA fiber mix had the weakest resistance to saltwater immersion and cyclic wetting and drying. PVA fibers, which have poor environmenesice ltwa wassignificantly degra and d bing ct in ma diearefiber mix exhibited good performance to saltw imsiod cy wet anddrying. PP fibers, which have relatively good resistance to aggressive environm, wanot degraded in sater imrsir fr ay be summarized as follows: ap act was uch echa tha ncre atr nd refore m ost rate s tra ort elet s m rials d th erio n mechanism ied he m crit transpo rt m or d ini ning n th ess uire im ent indi determined to result in uniform damage throughout the specimen based on absorption test results. A ci ole in th te e s en was identified to accelerate transpo rt stres strib n in cula nd s e sh speci sting. T is f ing wed test f 25 st b or s. DT s en uni adv ges tran rtin lete ma ls and obtaining uniformly deteriorated stress distribution at the failure surface compared with conventional beam specimen. A 100 was 25.4 mm thickness wit ended st ive ssess effe f f s on erio n of C. ith ct tension mode by low loading ra ntly atio d hig ate efle sub uen the dene ment past hich com n pr m a ersion due to excellent bonding in the matrix. In addition, steel corrosion reaction during cyclicwetting and drying in saltwater contributed to increased resistance of fiber pull-out from embedded m tal r stan to sa ter, ded goo ond effe the trix sapp d. PP ater mer n an clic ting ents s altw me on o om repeated shrinkage effect. The increased 173

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density in pores from continuous imlt crystallization from cyclic wetting and drying both concking. ditioning time and also more clearly identified the failure mechanism of fibers subjected to conditioning thnal beam appro more en and uniform stress distribution on the fracture plane. The recte may p reasonlution to re conventional beam approach for evaluation of failure mechanisd w iss mersion and sa tributed to improve resistance of PP fiber to cra The repeated loading approach with thin indirect tension mode significantly reduced the con an the conventio ach because of a uniformindi ly damaged specim tensile mod rovide a able so eplace th ms associate ith durability ue. 174

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CHAPTER 7 FINDINGS, CONCLUSIONS, AND RECOMMENDATIONS 7.1 Summary of Findings An experimental program was performed to examine the effects of fiber type on concrete durability from measurements of both the fresh and hardened concrete properties. The fresh fibrous concrete was characterized by its slump, inverted slump time, Vebe time, and air content. Mechanical properties included compressive, splitting tensile, pressure tension, beam, and indirect tension testing. In addition, volume of voids, water permeability, absorption, chloride diffusion, surface resistivity, and steel bar corrosion tests were performed to evaluate transport properties of deleterious materials into concrete. Finally, an energy dispersive X-ray spectrometer, operating in tandem with scanning electron microscopy (SEM) was used to allow elemental and chemical analysis of deteriorated specimens. Significant reduction in workability resulting from the addition of PP, PVA, and steel fibers to concrete can be clearly measured. Both inverted slump cone and Vebe time test methods were more accurate and sensitive to presence of fibers than conventional slump test. However, the inverted slump cone test had the greatest sensitivity to distinguish between workability of different fiber types and involved less expensive equipment than the Vebe test. Tests results from the experimental investigation of transport properties indicated that the addition of fibers improved resistance of mass transport of deleterious materials. However, among the fiber types, the addition of steel fibers had the best ability to resist mass transport of deleterious materials in concrete. Mass transport by capillary action in FRC was much faster than that either permeation or diffusion processes. It is evident that absorption can be a critical transport mechanism in terms of accelerating the ingress of deleterious materials into concrete. Therefore, it appears that the most effective approach for achieving uniformly damaged 175

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specimens for evaluation is through the use of repeated absorption by wetting and drying combined with a specimen geometry that ensures uniformity of absorption within a reasonable amount of time. Peak strengths were affected mainly by the matrix not the fibers. Only the addition of hooked-end steel fibers with high modulus and high tensile strength resulted in a slight improvement in peak strengths. A large number of pre-cracked and un-cracked beams consisting of different fiber types and two Classes of concrete were exposed to simulated Florida environments for 27 months. Conventional flexural beam testing was performed to assess the effect of fibers on deterioration of FRC. Unfortunately, serious problems were identified regarding the effectiveness of both the conditioning and test methods used. Effect of fibers on cracking resistance could not be assessed based on test results from either average residual strength (ASTM C 1399) or flexural performance (ASTM C 1609) tests. It was determined that the conventional flexural beam approach resulted in non-uniform degradation and stress/strain distributions through the cross-section. Also, beam tests generally resulted in multiple cracks initiating at the bottom of the specimen and instability subsequent to matrix cracking. These critical factors significantly affected the pull-out mechanism of fibers and disturbed the evaluation of failure during post-cracking. Observations and test results from SEM and EDS analysis were probably also affected by problems associated with the flexural beam approach. Beam specimens also can be problems in terms of achieving proper conditioning using cyclic wetting and drying. It was found that cyclic wetting and drying only degrades the outer half-inch shell of beams, which results in non-uniformly damaged cross-sections. 176

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These results clearly indicated the need to develop more effective conditioning methods to achieve uniformly damaged specimens. In addition, more effective test methods were required to clearly evaluate the effects of fibers on resistance to chemical deterioration. Based on findings and observations, the indirect tensile test mode was introduced, which allowed for accelerated transport of deleterious materials and resulted in a uniformly degraded cross-section and uniform stress/strain distributions. Absorption by capillary suction was identified as the most critical transport mechanism for determining an effective damage conditioning method and specimen thickness. A 14-day wetting and drying cyclic conditioning procedure was determined to result in uniform damage throughout the specimen based on absorption test results. A 44 inch square specimen one inch thick, which was sliced from beam specimens exposed to lime water immersion, with a hole cored at its center was proposed to most effectively assess the effect of fibers on deterioration of FRC. The effects of fiber type on resistance to chemical degradation were clearly observed from the SuperPaveTM IDT test methods. In addition, the approach resulted in a great reduction of specimen volume, labor, and cost. IDT strength test performed at a slow loading rate was determined to minimize the high energy dissipation and the high rate of deflection subsequent to matrix cracking. Additionally, repeated loading test showed superior advantages to assess deterioration of FRC by evaluating averaged horizontal deformation and increase in horizontal resilient deformation ratio. It was determined that the following issues should be considered to properly evaluate the effect of fiber type on durability of FRC: Determination of fresh properties to evaluate workability related to fiber distribution in fresh mixes. 177

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Determination of transport properties to evaluate mass transport of deleterious materials and to identify conditioning methods and specimen thickness. Use of effective accelerated conditioning methods that results in uniformly degraded specimen Use of appropriate tensile testing systems that result in uniform stress/strain distributions at the failure surface. Use of slower loading rates to minimize problems associated with conventional IDT strength tests, which cause excessively high energy dissipation and rate of deflection at first cracking. Use of repeated loading testing after first cracking to evaluate rate of damage accumulation during post-cracking. The major findings regarding test methods and interpretation may be summarized as follows: Transport properties alone are not necessarily a good indicator of the effects of fibers on resistance to degradation. For example, the addition of PP fibers showing a high absorption rate had good resistance to saltwater immersion and cyclic wetting and drying. Transport properties can be used to identify appropriate conditioning and specimen thickness. Conventional beam test and interpretation were not suitable for evaluation of damage accumulation in FRC. The use of a heater/blower system and a reduced volume tank was effective in accelerating W/D conditioning. The major findings regarding effectiveness of different fibers may be summarized as follows: The addition of PP fibers at Vf = 0.5% exhibited excellent resistance to degradation in saltwater environments: little or no degradation effects were observed for polypropylene fiber reinforced concrete (PFRC) subjected to continuous saltwater immersion, while an improvement in properties was observed for PFRC subjected to saltwater wet/dry cycling. The addition of PVA fibers at Vf = 0.75% exhibited poor resistance to degradation in saltwater environments, particularly when subjected to continuous saltwater immersion and to a lesser extent, when subjected to saltwater wet/dry cycling. 178

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The addition of steel fibers at Vf = 1% to degradation in saltwater environments exhibited resistance somewhere between PFRC and PVAFRC. Considerable degradation effects were observed for steel fiber reinforced concrete (SFRC) subjected to continuous saltwater immersion, while no degradation and even a modest improvement in properties was observed for SFRC subjected to saltwater wet/dry cycling. SFRC accelerated the degradation of steel reinforcement in saltwater wet/dry cycling. The detrimental effect of acetic acid on aggregate and cement overwhelmed the degradation mechanism in swamp water environments. Therefore, the effect of fibers could not be distinguished for these environments. The effect of cellulose fibers at Vf = 0.1% could not be evaluated because good fiber distribution was not achieved in laboratory mixing. 7.2 Conclusions Based on various experimental investigations, conclusions are as follows: Inverted slump cone provides the most cost effective of the test methods evaluated to appropriately assess workability of FRC. Uniformly damaged specimens and tension tests are needed for proper assessment of resistance to degradation of fibers. IDT should be further developed by considering use of fiber in cement paste only in order to achieve better fiber distribution. PFRC provides the best resistance to degradation (best durability) for non-structural application in saltwater environment subjected to submerged and tidal zones. SFRC may be suitable in saltwater environment subjected to tidal zones, but should not be used if it will be in contact with reinforcing bars. PVAFRC should not be used in saltwater environment subjected to submerged and tidal zones. 7.3 Recommendations The recommendations are proposed as follows: IDT should be further developed to establish IDT application to FRC by evaluating the effects of multiple fiber types, fiber volume fractions, fiber aspect ratios, and fiber configurations. The procedures developed should be used to optimize performance and durability of FRC. 179

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APPENDIX A FRESH PROPERTY TEST RESULTS Table A-1. Fresh properties for Class II concrete Slump (in) Air Content (%) Mix Types Without With I.S.C (sec) Vebe (sec) Without With Air/Mix temp (F) Unit weight (lb/ft3) Mix PC 5.75 15 2 5.1 68/73 3679.56 Mix 1 8.50 1.50 3.1 Mix 1 PP 6.50 1.00 99 7 4.7 3.2 75/76 3781.44 Mix 2 6.50 1.50 4.2 Mix 1 PVA 6.50 1.50 85 6 4.2 4.2 77/75 3771.36 Mix 2 5.00 3.75 4.9 Mix 1 Cell 7.50 5.75 10 1 3.7 3.9 68/75 3761.28 Mix 2 3.25 0.75 3.1 Mix 1 Steel 3.25 0.75 87 9 4.0 2.8 72/79 3859.92 Mix 2 Table A-2. Fresh properties for Class V concrete Slump (in) Air Content (%) Mix Types Without With I.S.C (sec) Vebe (sec) Without With Air/Mix temp (F) Unit weight (lb/ft3) Mix PC 3.25 32 4 3.4 70/73 3853.44 Mix 1 7.75 2.00 2.8 Mix 1 PP 6.25 1.75 78 6 3.0 2.9 68/75 3870.45 Mix 2 8.50 4.25 2.5 Mix 1 PVA 8.00 2.75 67 4 2.7 2.0 68/73 3870.99 Mix 2 7.50 4.00 3.4 Mix 1 Cell 7.75 4.50 16 2 2.7 3.4 68/73 3813.84 Mix 2 7.00 2.50 2.7 Mix 1 Steel 6.50 1.75 59 5 2.8 2.4 75/76 3907.44 Mix 2 180

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APPENDIX B DENSITY, ABSORPTION, VOLUME OF VOIDS TEST RESUTLS Table B-1. Summary of the values of density, absorption, and voids obtained (Class II) Control Specimens Fiber Specimens Mix Type Specimen ID Absorption (%) Apparent Density (Mg/m3) Voids (%) Absorption (%) Apparent Density (Mg/m3) Voids (%) Control A 6.07 2.47 13.03 Control B 6.01 2.46 12.88 Control C 6.02 2.48 13.00 Average 6.03 2.47 12.97 S.D 0.03 0.01 0.08 PC C.O.V (%) 0.53 0.40 0.61 N/A PP_0.5%_A 6.40 2.51 13.83 6.61 2.51 14.23 PP_0.5%_B 6.37 2.50 13.72 6.58 2.54 14.31 PP_0.5%_C 6.44 2.50 13.85 6.57 2.53 14.23 Average 6.40 2.50 13.80 6.59 2.53 14.26 S.D 0.04 0.01 0.07 0.02 0.02 0.05 PP C.O.V (%) 0.55 0.23 0.51 0.32 0.60 0.32 PVA_0.75%_A 6.16 2.49 13.29 6.31 2.48 13.50 PVA_0.75%_B 6.04 2.50 13.11 6.25 2.52 13.59 PVA_0.75%_C 6.04 2.48 13.03 6.31 2.49 13.55 Average 6.08 2.49 13.14 6.29 2.50 13.55 S.D 0.07 0.01 0.13 0.03 0.02 0.05 PVA C.O.V (%) 1.14 0.40 1.01 0.55 0.83 0.33 CELL_0.1%_A 6.40 2.50 13.80 6.24 2.48 13.41 CELL_0.1%_B 6.09 2.49 13.15 6.31 2.51 13.67 CELL_0.1%_C 6.25 2.48 13.42 6.34 2.48 13.61 Average 6.25 2.49 13.46 6.30 2.49 13.56 S.D 0.16 0.01 0.33 0.05 0.02 0.14 Cell C.O.V (%) 2.52 0.40 2.43 0.81 0.70 1.00 ST_1%_A 5.99 2.47 12.90 5.47 2.54 12.19 ST_1%_B 6.06 2.47 13.01 5.46 2.54 12.18 ST_1%_C 6.00 2.48 12.98 5.34 2.55 11.98 Average 6.02 2.47 12.96 5.42 2.54 12.12 S.D 004 0.01 0.06 0.07 0.01 0.12 Steel C.O.V (%) 0.63 0.23 0.44 .1.33 0.23 0.98 181

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Table B-2. Summary of the values of density, absorption, and voids obtained (Class V) Control Specimens Fiber Specimens Mix Type Specimen ID Absorption (%) Apparent Density (Mg/m3) Voids (%) Absorption (%) Apparent Density (Mg/m3) Voids (%) Control A 5.61 2.47 12.16 Control B 5.67 2.49 12.37 Control C 5.50 2.49 12.05 Average 5.59 2.48 12.19 S.D 0.09 0.01 0.16 PC C.O.V (%) 1.54 0.46 1.33 N/A PP_0.5%_A 5.65 2.48 12.28 5.86 2.51 12.81 PP_0.5%_B 5.68 2.50 12.42 5.78 2.53 12.77 PP_0.5%_C 5.63 2.48 12.27 5.82 2.51 12.74 Average 5.65 2.49 12.32 5.82 2.52 12.77 S.D 0.03 0.01 0.06 0.04 0.01 0.04 PP C.O.V (%) 0.45 0.46 0.68 0.69 0.46 0.27 PVA_0.75%_A 5.97 2.50 12.97 6.16 2.53 13.48 PVA_0.75%_B 5.91 2.50 12.87 6.24 2.54 13.68 PVA_0.75%_C 5.90 2.50 12.85 6.20 2.55 13.63 Average 5.93 2.50 12.90 6.20 2.54 13.60 S.D (%) 0.04 0.00 0.06 0.04 0.01 0.10 PVA C.O.V (%) 0.64 0.00 0.50 0.65 0.39 0.77 CELL_0.1%_A 5.76 2.53 12.69 5.47 2.52 12.11 CELL_0.1%_B 5.73 2.49 12.47 5.68 2.49 12.38 CELL_0.1%_C 5.73 2.49 12.48 5.57 2.49 12.17 Average 5.74 2.50 12.55 5.57 2.50 12.22 S.D 0.02 0.02 0.12 0.11 0.02 0.14 Cell C.O.V (%) 0.30 0.99 0.99 1.88 0.69 1.16 ST_1%_A 6.02 2.51 13.14 5.88 2.56 13.10 ST_1%_B 6.07 2.52 13.25 5.80 2.58 13.01 ST_1%_C 6.03 2.51 13.15 5.62 2.56 13.01 Average 6.04 2.51 13.18 5.77 2.57 13.04 S.D 0.03 0.01 0.06 0.13 0.01 0.05 Steel C.O.V (%) 0.44 0.23 0.46 2.31 0.45 0.40 182

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APPENDIX C SURFACE RESISTIVITY TEST RESULTS Table C-1. Summary of the values of surface resistivity (k.cm) for Class II concrete: PC Reading Locations (Degree) Specimen ID Test Day 0 90 180 270 0 90 180 270 Ave Ave S.D C.O.V (%) Control A 7.3 6.7 6.8 6.8 7.4 6.6 6.8 6.8 6.9 Control B 6.9 6.9 6.3 7.0 7.0 6.9 6.7 7.2 6.9 Control C 28 6.9 6.8 6.8 7.0 6.8 7 6.7 6.9 6.9 6.9 0.02 0.3 Control A 8 7.4 7.1 7.2 7.8 7.3 7.0 7.2 7.4 Control B 7.5 7.5 6.9 7.5 7.7 7.6 7.0 7.4 7.4 Control C 56 7.2 7.2 7.4 7.3 7.2 7.6 7.3 7.3 7.3 7.4 0.04 0.5 Control A 7.8 7.5 7.2 7.1 7.4 7.5 7.8 7.3 7.5 Control B 7.3 7.5 7.2 7.5 7.3 7.3 7.4 7.5 7.4 Control C 91 7.3 7.7 7.2 7.5 7.7 7.9 7.3 7.5 7.5 7.4 0.07 0.9 Control A 12.3 12.0 11.3 11.1 11.8 12.0 11.2 11.0 11.6 Control B 11.7 11.6 10.8 11.4 11.2 11.9 10.8 11.5 11.4 Control C 182 11.4 11.9 11.1 11.1 11.4 11.7 11.1 11.4 11.4 11.4 0.12 1.1 Control A 14.2 12.8 13.3 13.3 12.5 12.7 13.0 12.7 13.1 Control B 13.0 13.9 13.3 13.0 13 12.4 13.0 13.1 13.1 Control C 364 13.1 13.2 13.5 13.0 12.8 12.9 13.1 12.8 13.1 13.1 0.02 0.1 Control A 14.1 13.6 12.2 15.2 13.3 13.9 12.6 13.2 13.5 Control B 13.3 13.5 14.3 13.7 13.7 13.4 13.7 13.4 13.6 Control C 540 13.5 13.5 12.8 12.6 13.6 13.6 12.3 13.4 13.2 13.4 0.24 1.8 Control A 13.2 13.0 13.0 11.2 13.9 13.0 12.6 10.8 12.6 Control B 14.1 13.1 13.4 12.6 15 13.5 13.3 13.2 13.5 Control C 730 14.0 14.2 13.2 13.6 13.6 13.5 13.5 13.0 13.6 13.2 0.56 4.2 Table C-2. Summary of the values of surface resistivity (k.cm) for Class II concrete: PP Reading Locations (Degree) Specimen ID Test Day 0 90 180 270 0 90 180 270 Ave 28 4.2 4.1 3.9 4.2 4.0 4.2 4.0 4.3 4.1 56 4.5 4.3 3.9 4.2 3.8 4.3 3.9 3.8 4.1 91 3.8 4.2 4.1 4.3 4.2 4.4 3.9 4.2 4.1 182 6.7 6.5 8.0 5.7 6.8 5.9 7.9 6.2 6.7 364 10.5 7.5 8.4 7.5 9.3 7.3 8.9 7.3 8.3 540 7.5 6.0 5.4 6.8 8.1 5.6 5.4 5.4 6.3 PP (Block) 730 5.5 6.1 6.1 6.4 5.6 6.1 5.9 6.0 6.0 Table C-3. Summary of the values of surface resistivity (k.cm) for Class II concrete: PVA Reading Locations (Degree) Specimen ID Test Day 0 90 180 270 0 90 180 270 Ave 28 4.1 4.9 5.0 4.6 4.4 4.9 5.0 4.8 4.7 56 4.8 5.3 4.8 4.9 5.0 5.3 5.2 5.1 5.1 91 4.8 5.5 5.7 5.4 4.8 5.2 5.9 6.0 5.4 182 8.5 8.0 7.1 7.6 8.2 7.8 7.1 7.5 7.5 364 11.0 10.9 9.6 9.1 11.5 9.5 9.5 9.9 10.1 540 8.1 6.5 5.5 6.4 7.1 6.1 5.6 6.2 6.4 PVA (Block) 730 6.2 5.5 6.0 6.0 5.6 5.7 6.1 6.0 5.9 183

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Table C-4. Summary of the values of surface resistivity (k.cm) for Class II concrete: cellulose fiber mixture (Cell) Reading Locations (Degree) Specimen ID Test Day 0 90 180 270 0 90 180 270 Ave 28 6.0 6.2 5.5 6.1 5.9 5.7 5.7 6.2 5.9 56 6.5 6.2 6.3 6.5 6.4 6.5 6.3 6.4 6.4 91 6.8 6.8 6.4 6.5 7.0 6.7 6.6 6.7 6.7 182 10.5 10.6 10 10.2 10.8 10.8 9.8 10.0 10.3 364 10.5 11.6 11.5 10.5 11.3 10.5 10.8 10.6 10.9 540 8.5 7.4 8.7 7.9 7.5 8.6 7.4 6.9 7.9 Cell (Block) 730 7.5 8.5 7.3 7.2 8.7 7.2 8.8 6.8 7.8 Table C-5 Summary of the values of surface resistivity (k.cm) for Class II concrete: steel fiber mixture (St) Reading Locations (Degree) Specimen ID Test Day 0 90 180 270 0 90 180 270 Ave 28 1.4 1.5 1.6 1.4 1.3 1.7 1.6 1.5 1.5 56 1.5 2.4 1.5 1.7 1.5 2.4 1.7 1.7 1.8 91 2.5 1.4 2.1 1.7 2.4 1.6 1.4 1.5 1.8 182 3.5 2.0 2.5 2.4 2.8 2.1 2.6 2.4 2.5 364 5.0 3.1 3.4 2.9 5.0 5.0 3.3 2.9 3.8 540 3.0 3.7 2.3 2.1 5.4 5.2 2.2 2.0 3.2 St (Block) 730 3.1 2.8 2.8 2.4 3.3 2.9 2.9 2.3 2.8 Table C-6. Summary of the values of surface resistivity (k.cm) for Class V concrete: plain concrete (PC) Reading Locations (Degree) Specimen ID Test Day 0 90 180 270 0 90 180 270 Ave Ave S.D C.O.V (%) Control A 9.4 8.6 9.3 8.6 9.4 8.8 9.3 8.3 9.0 Control B 9.2 9.0 9.0 8.8 9.4 9.0 9.2 9.2 9.1 Control C 28 9.4 9 9.2 8.7 9.2 9 9.2 8.8 9.1 9.0 0.07 0.8 Control A 9.8 9.4 9.6 10.3 9.9 9.5 9.7 10.1 9.8 Control B 9.9 9.8 9.6 9.7 9.9 9.7 10.1 9.6 9.9 Control C 56 10.2 9.4 10.2 9.3 10.4 9.5 10.2 9.2 10.2 9.8 0.01 0.1 Control A 10.4 10.1 9.6 9.8 9.8 9.6 9.9 10.1 9.9 Control B 9.8 9.9 10.2 10.5 10.5 10 10.2 10.6 10.2 Control C 91 10.5 10 10 9.5 10.6 10.1 10.4 9.3 10.1 10.1 0.15 1.5 Control A 9.7 10.4 10.4 10.8 9.6 10.6 10.1 10.6 10.3 Control B 10.7 10.5 10.2 10.3 10.5 10.6 10.1 10.4 10.4 Control C 182 11.1 10.2 10.6 9.8 11.3 10.2 10.7 10 10.5 10.4 0.11 1.0 Control A 13.3 13.1 14.7 13.4 13 13 13.3 13.9 13.5 Control B 13.5 13.4 13.6 13.1 13.3 13.4 13.1 13.3 13.3 Control C 364 13.3 13.1 13.3 13 13.5 13.4 13.2 13.4 13.3 13.4 0.10 0.7 Control A 14.1 13.6 12.2 15.2 15.2 13.9 12.6 13.2 13.8 Control B 13.3 15.4 14.3 13.7 13.7 13.4 13.7 13.4 13.9 Control C 540 13.5 15.4 12.8 12.6 15.2 15.2 12.3 17.4 14.3 14.0 0.29 2.1 Control A 13.9 13.0 16.0 11.2 13.9 15.2 12.6 10.8 13.3 Control B 14.1 13.1 13.4 12.6 15 13.5 13.3 13.2 13.5 Control C 730 14 14.2 14.9 13.6 13.6 13.5 16.2 13.0 14.1 13.7 0.42 3.0 184

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Table C-7. Summary of the values of surface resistivity (k.cm) for Class V concrete: polypropylene fiber mixture (PP) Reading Locations (Degree) Specimen ID Test Day 0 90 180 270 0 90 180 270 Ave 28 5.2 5.3 4.9 5.0 5.3 5.0 5.1 5.1 5.1 56 6.5 5.3 5.4 5.7 6.0 5.6 5.5 6.1 5.8 91 6.4 5.4 5.8 5.7 5.9 5.9 6.0 5.8 5.9 182 6.5 6.2 6.1 6.3 6.7 6.3 6.6 6.9 6.5 364 6.7 7.5 7.8 7.1 6.9 7.6 7.3 7.3 7.3 540 8.7 6.8 7.5 7.2 8.2 6.5 7.5 7.5 7.5 PP (Block) 730 6.9 8.3 7.5 7.2 7.1 7.6 7.8 7.5 7.5 Table C-8. Summary of the values of surface resistivity (k.cm) for Class V concrete: polyvinyl alcohol fiber mixture (PVA) Reading Locations (Degree) Specimen ID Test Day 0 90 180 270 0 90 180 270 Ave 28 4.9 5.1 5.3 5.3 4.8 5.2 5.4 5.3 5.2 56 5.2 5.6 5.6 5.6 5.5 5.6 5.8 5.6 5.6 91 6.3 5.7 6.2 5.5 6.3 5.9 6.4 5.9 6.0 182 7.0 6.3 6.4 6.1 6.4 6.0 6.1 6.2 6.3 364 7.9 7.7 8.2 7.9 8.4 7.7 8.4 7.6 8.0 540 7.2 6.7 7.7 6.9 7.1 6.7 8 7.4 7.2 PVA (Block) 730 8.4 7.3 8.9 8.7 8.2 7.2 8.2 8.6 8.2 Table C-9. Summary of the values of surface resistivity (k.cm) for Class V concrete: cellulose fiber mixture (Cell) Reading Locations (Degree) Specimen ID Test Day 0 90 180 270 0 90 180 270 Ave 28 6.1 5.8 6.4 6.1 6.3 6.0 6.4 6.2 6.2 56 6.0 5.9 5.7 5.8 5.8 5.9 5.9 5.6 5.8 91 6.2 5.4 5.5 6.3 5.9 5.4 5.6 5.9 5.8 182 8.4 8.6 8.4 8.8 8.5 8.5 8.5 8.4 8.5 364 13.2 11.4 10.8 11.5 11.1 12.3 10.0 11.1 11.4 540 6.3 6.5 7.2 7.9 6.6 7.3 7.4 6.9 7.0 Cell (Block) 730 7 7.2 7.3 7.2 7.1 7.2 7.2 6.8 7.1 Table C-10. Summary of the values of surface resistivity (k.cm) for Class V concrete: steel fiber mixture (St) Reading Locations (Degree) Specimen ID Test Day 0 90 180 270 0 90 180 270 Ave 28 2.4 2.0 3.6 1.9 2.5 2.6 3.1 1.8 2.5 56 3.1 4.0 2.4 2.2 2.5 3.0 2.5 2.3 2.8 91 2.7 3.0 3.7 2.3 3.0 2.6 4.0 2.9 3.0 182 3.7 4.3 4.5 5.3 3.4 4.2 4.6 4.7 4.3 364 6.8 5.8 5.3 4.1 5.8 4.6 4.8 5.3 5.3 540 4.6 5.5 4.4 6.1 5.6 4.5 3.5 5.6 5.0 St (Block) 730 3.4 4.4 3.5 6.8 3.4 3.5 2.5 5.6 4.1 185

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APPENDIX D WATER PERMEABILITY TEST RESULTS Table D-1. Summary of the values of water permeability coefficient obtained for Classes II/V concrete Class II Concrete Class V Concrete Mix Type Specimen ID Control (x10-13 m/s) Fiber (x10-13 m/s) Control (x10-13 m/s) Fiber (x10-13 m/s) Control A 2.83 2.34 Control B 2.17 Control C 3.19 Average 3.01 2.26 S.D 0.25 0.12 PC C.O.V (%) 8.46 N/A 5.33 N/A PP_0.5%_A 3.37 3.12 2.48 2.02 PP_0.5%_B 3.46 2.90 2.92 2.37 PP_0.5%_C 2.96 3.25 Average 3.26 3.09 2.70 2.20 S.D 0.27 0.18 0.31 0.25 PP C.O.V (%) 8.17 5.73 11.52 11.28 PVA_0.75%_A 2.50 2.97 2.15 1.80 PVA_0.75%_B 2.41 3.05 1.90 2.09 PVA_0.75%_C 2.69 2.92 1.92 1.88 Average 2.53 2.98 1.99 1.92 S.D 0.14 0.07 0.14 0.15 PVA C.O.V 5.64 2.20 6.98 7.79 CELL_0.1%_A 4.31 3.32 2.24 2.55 CELL_0.1%_B 4.31 3.58 2.53 2.25 CELL_0.1%_C 4.41 3.37 2.35 Average 4.34 3.42 2.39 2.38 S.D 0.06 0.14 0.21 0.15 Cell C.O.V (%) 1.33 4.03 8.60 6.41 ST_1%_A 2.62 2.02 1.73 ST_1%_B 3.92 2.28 1.84 1.78 ST_1%_C 2.28 1.71 1.72 Average 3.92 2.39 1.86 1.74 S.D 0.20 0.16 0.03 Steel C.O.V (%) 8.20 8.38 1.84 186

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APPENDIX E ABSORPTION TEST RESULTS Table E-1. Summary of the values of absorption rate obtained for Class II concrete Control Specimens Fiber Specimens Mix Type Specimen ID Initial (x10-2 mm/s0.5) Second (x10-2 mm/s0.5) Initial (x10-2 mm/s0.5) Second (x10-2 mm/s0.5) Control A 2.48 1.34 Control B 2.45 1.48 Control C 2.43 1.53 Average 2.45 1.45 S.D 0.0002 0.001 PC C.O.V (%) 0.93 6.82 N/A N/A PP_0.5%_A 2.44 1.48 2.48 1.76 PP_0.5%_B 2.15 1.43 2.59 1.86 PP_0.5%_C Average 2.29 1.45 2.54 1.81 S.D 0.0021 0.0003 0.0008 0.0007 PP C.O.V (%) 9.18 2.14 3.04 3.87 PVA_0.75%_A 1.79 1.02 1.75 1.22 PVA_0.75%_B 1.82 1.03 1.79 1.29 PVA_0.75%_C Average 1.81 1.03 1.77 1.26 S.D 0.0002 0.0001 0.0003 0.0005 PVA C.O.V (%) 1.33 0.62 1.76 4.28 CELL_0.1%_A 2.19 1.59 2.40 1.63 CELL_0.1%_B 2.38 1.60 2.37 1.68 CELL_0.1%_C 2.15 1.55 Average 2.24 1.58 2.39 1.65 S.D 0.0012 0.0003 0.0002 0.0004 Cell C.O.V (%) 5.42 1.73 0.83 2.22 ST_1%_A 1.90 1.34 ST_1%_B 2.09 1.27 1.98 1.43 ST_1%_C 2.30 1.44 Average 2.20 1.36 1.94 1.39 S.D 0.0015 0.0012 0.0006 0.0006 Steel C.O.V (%) 6.73 8.87 2.91 4.59 187

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Table E-2. Summary of the values of absorption rate obtained for Class V concrete Control Specimens Fiber Specimens Mix Type Specimen ID Initial (x10-2 mm/s0.5) Second (x10-2 mm/s0.5) Initial (x10-2 mm/s0.5) Second (x10-2 mm/s0.5) Control A 1.71 0.98 Control B 1.69 0.96 Control C 1.75 0.94 Average 1.72 0.96 S.D 0.0003 0.0002 PC C.O.V (%) 1.65 2.35 N/A N/A PP_0.5%_A 1.02 0.46 1.92 1.05 PP_0.5%_B 1.14 0.51 PP_0.5%_C 2.14 1.16 Average 1.08 0.48 2.03 1.10 S.D 0.0009 0.0003 0.0015 0.0008 PP C.O.V (%) 8.05 6.90 7.62 7.06 PVA_0.75%_A PVA_0.75%_B 1.17 0.97 1.26 0.91 PVA_0.75%_C 1.38 1.06 1.44 0.95 Average 1.27 1.02 1.35 0.93 S.D 0.0015 0.0006 0.0012 0.0003 PVA C.O.V (%) 11.48 5.85 9.06 3.50 CELL_0.1%_A 1.17 0.65 1.38 0.81 CELL_0.1%_B 1.22 0.67 CELL_0.1%_C 1.38 0.85 Average 1.20 0.66 1.38 0.83 S.D 0.0003 0.0002 0.00002 0.0003 Cell C.O.V (%) 2.78 2.67 0.15 4.18 ST_1%_A 1.46 0.93 ST_1%_B 1.22 0.64 ST_1%_C 1.31 0.72 1.63 0.96 Average 1.26 0.68 1.55 0.95 S.D 0.0007 0.0005 0.0012 0.0002 Steel C.O.V (%) 5.16 8.00 7.95 2.02 188

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APPENDIX F BULK DIFFUSION TEST RESULTS Table F-1. Summary of the values of coefficient of chloride diffusion obtained for Class II concrete Class II Concrete Class V Concrete Mix Type Specimen ID Diffusion Coefficient (x10-12 m2/s) Diffusion Coefficient (x10-12 m2/s) Control A 7.28 Control B 16.10 7.92 Control C 17.55 8.08 Average 16.83 7.76 S.D 1.028 0.42 PC C.O.V (%) 6.11 5.42 PP_0.5%_A 5.87 PP_0.5%_B 17.17 6.28 PP_0.5%_C 17.96 6.86 Average 17.57 6.33 S.D 0.559 0.50 PP C.O.V (%) 3.18 7.83 PVA_0.75%_A PVA_0.75%_B 11.37 7.35 PVA_0.75%_C 12.23 6.64 Average 11.80 6.99 S.D 0.61 0.50 PVA C.O.V (%) 5.13 7.20 CELL_0.1%_A 11.32 CELL_0.1%_B 14.84 11.87 CELL_0.1%_C 17.29 Average 16.07 11.60 S.D 1.73 0.39 Cell C.O.V (%) 10.78 3.37 ST_1%_A 6.47 5.27 ST_1%_B ST_1%_C 6.04 5.91 Average 6.26 5.59 S.D 0.30 0.45 Steel C.O.V (%) 4.86 8.11 189

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Table F-2. Summary of the values of 1-year bulk diffusion chloride profile for Class II concrete NaCl (lb/yd3) Mix Type Specimen ID Depth (in) A B C AVG 0.0" 0.5" 30.708 30.709 30.764 30.727 0.5" 1.0" 18.086 18.537 18.227 18.284 1.0" 1.5" 11.174 10.885 11.194 11.085 1.5" 2.0" 7.258 7.359 7.225 7.281 2.0" 2.5" 3.385 3.296 3.376 3.352 2.5" 3.0" 0.660 0.709 0.711 0.693 Control B 3.0" 3.5" 0.194 0.184 0.174 0.184 0.0" 0.5" 34.833 34.388 34.162 34.461 0.5" 1.0" 22.254 22.971 22.597 22.607 1.0" 1.5" 13.189 12.686 13.185 13.120 1.5" 2.0" 8.118 7.992 7.911 8.007 2.0" 2.5" 4.335 4.412 4.624 4.457 2.5" 3.0" 1.316 1.305 1.336 1.319 PC Control C 3.0" 3.5" 0.298 0.319 0.289 0.302 0.0" 0.5" 30.195 30.525 30.116 30.279 0.5" 1.0" 18.472 18.442 18.802 18.572 1.0" 1.5" 11.416 11.031 11.177 11.208 1.5" 2.0" 7.427 7.439 7.309 7.392 2.0" 2.5" 4.005 4.057 4.048 4.037 2.5" 3.0" 1.062 1.043 1.073 1.059 PP_0.5%_B 3.0" 3.5" 0.332 0.335 0.338 0.335 0.0" 0.5" 25.992 26.675 26.286 26.318 0.5" 1.0" 16.283 16.446 16.446 16.392 1.0" 1.5" 10.746 10.584 10.621 10.650 1.5" 2.0" 6.555 6.625 6.796 6.659 2.0" 2.5" 3.385 3.188 3.207 3.260 2.5" 3.0" 0.959 0.911 0.969 0.946 PP PP_0.5%_C 3.0" 3.5" 0.283 0.317 0.301 0.300 0.0" 0.5" 34.945 34.261 34.668 34.625 0.5" 1.0" 18.620 18.972 18.908 18.833 1.0" 1.5" 10.280 10.178 10.379 10.279 1.5" 2.0" 5.485 5.205 5.476 5.389 2.0" 2.5" 1.387 1.393 1.393 1.391 2.5" 3.0" 0.289 0.293 0.304 0.295 PVA_0.75%_B 3.0" 3.5" 0.268 0.272 0.276 0.272 0.0" 0.5" 33.392 32.979 33.661 33.344 0.5" 1.0" 19.730 18.958 19.660 19.449 1.0" 1.5" 10.399 10.199 10.227 10.275 1.5" 2.0" 5.577 5.756 5.510 5.614 2.0" 2.5" 1.402 1.339 1.351 1.364 2.5" 3.0" 0.307 0.300 0.286 0.298 PVA PVA_0.75%_C 3.0" 3.5" 0.284 0.296 0.295 0.292 190

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Table F-2. Continued NaCl (lb/yd3) Mix Type Specimen ID Depth (in) A B C AVG 0.0" 0.5" 34.636 34.642 34.251 34.510 0.5" 1.0" 19.787 20.326 19.743 19.952 1.0" 1.5" 11.728 11.752 11.738 11.739 1.5" 2.0" 7.206 6.600 7.116 6.974 2.0" 2.5" 3.854 4.096 4.453 4.134 2.5" 3.0" 1.120 1.150 1.129 1.133 Cell_0.1%_B 3.0" 3.5" 0.369 0.371 0.389 0.376 0.0" 0.5" 25.261 24.939 24.149 25.116 0.5" 1.0" 16.976 16.189 16.845 16.670 1.0" 1.5" 10.044 10.308 10.459 10.270 1.5" 2.0" 5.885 5.944 6.091 5.973 2.0" 2.5" 2.534 2.503 2.543 2.527 2.5" 3.0" 0.434 0.501 0.479 0.471 Cell Cell_0.1%_C 3.0" 3.5" 0.259 0.270 0.253 0.261 0" 0.125" 44.404 44.725 44.555 44.561 0.125" 0.25" 37.053 36.870 36.784 36.903 0.25" 0.375" 28.695 28.810 28.619 28.708 0.375" 0.5" 23.639 23.371 23.090 23.367 0.5" 1" 14.343 14.792 14.686 14.607 1" 1.5" 7.159 7.575 7.384 7.373 St_1%_A 1.5" 2" 1.403 1.407 1.427 1.413 0.0" 0.5" 38.218 37.589 38.039 37.949 0.5" 1.0" 15.412 15.271 15.087 15.257 1.0" 1.5" 7.127 7.291 7.268 7.229 1.5" 2.0" 1.539 1.567 1.562 1.556 2.0" 2.5" 0.285 0.267 0.288 0.280 2.5" 3.0" 0.247 0.243 0.244 0.245 Steel St_1%_C 3.0" 3.5" 0.296 0.242 0.225 0.254 191

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Table F-3. Summary of the values of 1-year bulk diffusion chloride profile for Class V concrete NaCl (lb/yd3) Mix Type Specimen ID Depth (in) A B C AVG 0" 0.125" 43.960 43.960 43.858 43.993 0.125" 0.25" 34.481 34.481 34.774 34.597 0.25" 0.375" 28.458 28.458 28.696 28.577 0.375" 0.5" 24.725 24.725 24.751 24.742 0.5" 1" 16.290 16.290 16.377 16.335 1" 1.5" 6.067 6.067 6.106 6.001 Control A 1.5" 2" 0.770 0.770 0.784 0.772 0.0" 0.5" 35.306 34.848 34.519 34.891 0.5" 1.0" 18.311 18.509 18.352 18.391 1.0" 1.5" 7.346 7.490 7.489 7.442 1.5" 2.0" 1.177 1.202 1.126 1.168 2.0" 2.5" 0.371 0.353 0.332 0.352 2.5" 3.0" 0.468 0.452 0.470 0.463 Control B 3.0" 3.5" 0.399 0.393 0.385 0.392 0.0" 0.5" 37.365 37.808 37.515 37.563 0.5" 1.0" 19.823 19.535 19.421 19.593 1.0" 1.5" 8.164 8.387 8.429 8.327 1.5" 2.0" 1.561 1.576 1.558 1.565 2.0" 2.5" 0.490 0.488 0.459 0.479 2.5" 3.0" 0.441 0.505 0.489 0.478 PC Control C 3.0" 3.5" 0.388 0.441 0.406 0.412 0" 0.125" 38.179 38.179 38.169 38.078 0.125" 0.25" 30.835 30.835 31.206 31.024 0.25" 0.375" 25.536 25.536 25.799 25.688 0.375" 0.5" 21.937 21.937 22.132 22.133 0.5" 1" 13.427 13.427 13.420 13.440 1" 1.5" 3.079 3.079 3.172 3.093 PP_0.5%_A 1.5" 2" 0.283 0.283 0.290 0.283 0.0" 0.5" 34.341 34.988 34.697 34.675 0.5" 1.0" 16.263 16.189 16.385 16.279 1.0" 1.5" 5.298 5.185 5.176 5.220 1.5" 2.0" 0.466 0.459 0.469 0.465 2.0" 2.5" 0.193 0.198 0.212 0.201 2.5" 3.0" 0.213 0.201 0.203 0.206 PP_0.5%_B 3.0" 3.5" 0.216 0.208 0.225 0.216 0.0" 0.5" 34.840 34.410 34.548 34.599 0.5" 1.0" 17.112 17.200 17.307 17.206 1.0" 1.5" 5.863 5.912 5.905 5.893 1.5" 2.0" 0.536 0.548 0.524 0.536 2.0" 2.5" 0.255 0.267 0.205 0.242 2.5" 3.0" 0.441 0.432 0.471 0.448 PP PP_0.5%_C 3.0" 3.5" 0.204 0.258 0.209 0.224 192

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Table F-3. Continued NaCl (lb/yd3) Mix Type Specimen ID Depth (in) A B C AVG 0.0" 0.5" 31.916 31.643 31.366 31.642 0.5" 1.0" 15.327 15.327 15.276 15.310 1.0" 1.5" 6.423 6.642 6.624 6.563 1.5" 2.0" 1.117 1.095 1.092 1.101 2.0" 2.5" 0.306 0.302 0.301 0.303 2.5" 3.0" 0.313 0.283 0.288 0.295 PVA_0.75%_B 3.0" 3.5" 0.453 0.485 0.488 0.475 0.0" 0.5" 34.975 34.409 35.139 34.841 0.5" 1.0" 16.489 16.255 16.725 16.490 1.0" 1.5" 6.194 6.241 5.543 5.993 1.5" 2.0" 0.581 0.574 0.577 0.577 2.0" 2.5" 0.364 0.350 0.352 0.355 2.5" 3.0" 0.588 0.618 0.590 0.599 PVA PVA_0.75%_C 3.0" 3.5" 0.315 0.313 0.310 0.313 0" 0.125" 40.091 40.091 40.173 40.264 0.125" 0.25" 34.985 34.985 35.033 35.101 0.25" 0.375" 28.380 28.380 28.103 28.183 0.375" 0.5" 21.742 21.742 22.041 22.033 0.5" 1" 17.539 17.539 17.484 17.496 1" 1.5" 9.974 9.974 9.952 9.931 Cell_0.1%_A 1.5" 2" 5.029 5.029 5.198 5.086 0.0" 0.5" 30.138 30.290 29.596 30.008 0.5" 1.0" 28.970 29.548 29.728 29.415 1.0" 1.5" 16.220 16.383 16.171 16.258 1.5" 2.0" 6.767 6.208 6.549 6.508 2.0" 2.5" 1.024 0.978 1.050 1.017 2.5" 3.0" 0.217 0.220 0.239 0.225 Cell Cell_0.1%_B 3.0" 3.5" 0.266 0.251 0.238 0.252 0" 0.125" 45.617 45.617 46.154 46.040 0.125" 0.25" 38.458 38.458 37.903 38.123 0.25" 0.375" 30.001 30.001 29.868 29.869 0.375" 0.5" 23.177 23.177 23.193 23.095 0.5" 1" 15.487 15.487 15.372 15.439 1" 1.5" 4.207 4.207 3.972 4.135 St_1%_A 1.5" 2" 0.325 0.325 0.275 0.312 0.0" 0.5" 28.131 27.972 28.048 28.050 0.5" 1.0" 13.016 12.966 12.827 12.936 1.0" 1.5" 3.638 3.617 3.557 3.604 1.5" 2.0" 0.471 0.432 0.419 0.441 2.0" 2.5" 0.326 0.295 0.305 0.309 2.5" 3.0" 0.306 0.305 0.290 0.300 Steel St_1%_C 3.0" 3.5" 0.252 0.279 0.260 0.264 193

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0 20 40 60 80 100 0 20 40 60 PC-Control B for 1-Year Bulk DiffusionDepth (mm)Chloride Content (lb/yd^3) Diffusion(m^2/sec)1.610E-11Background(lb/yd^3)0.213Surface(lb/yd^3)35.570R^2 Value0.9966 0 20 40 60 80 100 0 20 40 60 PC-Control C for 364-Day Bulk DiffusionDepth (mm)Chloride Content (lb/yd^3) Diffusion(m^2/sec)1.755E-11Background(lb/yd^3)0.213Surface(lb/yd^3)40.247R^2 Value0.9991 0 20 40 60 80 100 0 20 40 60 PP_0.5%_B for 364-Day Bulk DiffusionDepth (mm)Chloride Content (lb/yd^3) Diffusion(m^2/sec)1.717E-11Background(lb/yd^3)0.285Surface(lb/yd^3)34.814R^2 Value0.9968 0 20 40 60 80 100 0 20 40 60 PP_0.5%_C for 364-Day Bulk DiffusionDepth (mm)Chloride Content (lb/yd^3) Diffusion(m^2/sec)1.796E-11Background(lb/yd^3)0.285Surface(lb/yd^3)30.307R^2 Value0.9978 0 20 40 60 80 100 0 20 40 60 PVA_0.75%_B for 364-Day Bulk DiffusionDepth (mm)Chloride Content (lb/yd^3) Diffusion(m^2/sec)1.137E-11Background(lb/yd^3)0.216Surface(lb/yd^3)41.926R^2 Value0.9983 0 20 40 60 80 100 0 20 40 60 PVA_0.75%_C for 364-Day Bulk DiffusionDepth (mm)Chloride Content (lb/yd^3) Diffusion(m^2/sec)1.226E-11Background(lb/yd^3)0.216Surface(lb/yd^3)40.356R^2 Value0.9991 Figure F-1. Regression analysis of bulk diffusion for Class II concrete 194

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0 20 40 60 80 100 0 20 40 60 Cell_0.1%_B for 364-Day Bulk DiffusionDepth (mm)Chloride Content (lb/yd^3) Diffusion(m^2/sec)1.484E-11Background(lb/yd^3)0.268Surface(lb/yd^3)40.171R^2 Value0.9966 0 20 40 60 80 100 0 20 40 60 Cell_0.1%_C for 364-Day Bulk DiffusionDepth (mm)Chloride Content (lb/yd^3) Diffusion(m^2/sec)1.729E-11Background(lb/yd^3)0.268Surface(lb/yd^3)29.615R^2 Value0.9992 0 20 40 60 80 100 0 20 40 60 St_1%_A for 364-Day Bulk DiffusionDepth (mm)Chloride Content (lb/yd^3) Diffusion(m^2/sec)6.474E-12Background(lb/yd^3)0.304Surface(lb/yd^3)42.831R^2 Value0.9947 0 20 40 60 80 100 0 20 40 60 St_1%_C for 364-Day Bulk DiffusionDepth (mm)Chloride Content (lb/yd^3) Diffusion(m^2/sec)6.044E-12Background(lb/yd^3)0.304Surface(lb/yd^3)50.313R^2 Value0.9977 Figure F-1. Continued 195

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0 20 40 60 80 100 0 20 40 60 PC_Control_A for 364-Day Bulk DiffusionDepth (mm)Chloride Content (lb/yd^3) Diffusion(m^2/sec)7.282E-12Background(lb/yd^3)0.243Surface(lb/yd^3)41.254R^2 Value0.9990 0 20 40 60 80 100 0 20 40 60 PC_Control_B for 364-Day Bulk DiffusionDepth (mm)Chloride Content (lb/yd^3) Diffusion(m^2/sec)7.919E-12Background(lb/yd^3)0.243Surface(lb/yd^3)45.170R^2 Value0.9992 0 20 40 60 80 100 0 20 40 60 PC_Control_C for 364-Day Bulk DiffusionDepth (mm)Chloride Content (lb/yd^3) Diffusion(m^2/sec)8.075E-12Background(lb/yd^3)0.243Surface(lb/yd^3)48.364R^2 Value0.9994 0 20 40 60 80 100 0 20 40 60 PP_0.5%_A for 364-Day Bulk DiffusionDepth (mm)Chloride Content (lb/yd^3) Diffusion(m^2/sec)5.868E-12Background(lb/yd^3)0.236Surface(lb/yd^3)38.517R^2 Value0.9988 0 20 40 60 80 100 0 20 40 60 PP_0.5%_B for 364-Day Bulk DiffusionDepth (mm)Chloride Content (lb/yd^3) Diffusion(m^2/sec)6.277E-12Background(lb/yd^3)0.236Surface(lb/yd^3)46.407R^2 Value0.9995 0 20 40 60 80 100 0 20 40 60 PP_0.5%_C for 364-Day Bulk DiffusionDepth (mm)Chloride Content (lb/yd^3) Diffusion(m^2/sec)6.855E-12Background(lb/yd^3)0.236Surface(lb/yd^3)45.768R^2 Value0.9992 Figure F-2. Regression analysis of bulk diffusion for Class V concrete 196

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0 20 40 60 80 100 0 20 40 60 PVA_0.75%_B for 364-Day Bulk DiffusionDepth (mm)Chloride Content (lb/yd^3) Diffusion(m^2/sec)7.347E-12Background(lb/yd^3)0.202Surface(lb/yd^3)41.101R^2 Value0.9994 0 20 40 60 80 100 0 20 40 60 PVA_0.75%_C for 364-Day Bulk DiffusionDepth (mm)Chloride Content (lb/yd^3) Diffusion(m^2/sec)6.635E-12Background(lb/yd^3)0.202Surface(lb/yd^3)46.132R^2 Value0.9994 0 20 40 60 80 100 0 20 40 60 Cell_0.1%_A for 364-Day Bulk DiffusionDepth (mm)Chloride Content (lb/yd^3) Diffusion(m^2/sec)1.132E-11Background(lb/yd^3)0.211Surface(lb/yd^3)37.428R^2 Value0.9902 0 20 40 60 80 100 0 20 40 60 Cell_0.1%_B for 364-Day Bulk DiffusionDepth (mm)Chloride Content (lb/yd^3) Diffusion(m^2/sec)1.187E-11Background(lb/yd^3)0.211Surface(lb/yd^3)61.204R^2 Value0.9978 0 20 40 60 80 100 0 20 40 60 St_1%_A 364-Day Bulk DiffusionDepth (mm)Chloride Content (lb/yd^3) Diffusion(m^2/sec)5.267E-12Background(lb/yd^3)0.243Surface(lb/yd^3)46.164R^2 Value0.9964 0 20 40 60 80 100 0 20 40 60 CPR1 (Sample A) 364-Day Bulk DiffusionDepth (mm)Chloride Content (lb/yd^3) Diffusion(m^2/sec)5.909E-12Background(lb/yd^3)0.243Surface(lb/yd^3)37.934R^2 Value0.9995 Figure F-2. Continued 197

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APPENDIX G MECHANICAL PROPERTIES TEST RESULTS Table G-1. Summary of the values of f'c fst, and fpt obtained for Class II concrete Compressive Strength (ksi) Splitting Tensile Strength (psi) Mix Type Specimen ID Control Fiber Control Fiber Pressure Tension (psi) Control A 8.12 722.00 817.22 Control B 7.98 737.39 834.85 Control C 8.51 706.10 851.47 Average 8.20 721.83 834.51 S.D 0.22 15.65 17.13 PC C.O.V (%) 2.74 N/A 2.17 N/A 2.05 PP_0.5%_A 8.32 7.87 659.30 725.84 732.15 PP_0.5%_B 8.20 8.42 653.78 608.26 756.57 PP_0.5%_C 8.60 8.20 590.59 626.28 725.36 Average 8.37 8.09 634.56 653.46 738.03 S.D 0.21 0.27 38.18 63.33 16.41 PP C.O.V (%) 2.49 3.34 6.02 9.69 2.22 PVA_0.75%_A 8.25 8.25 604.50 655.44 734.58 PVA_0.75%_B 8.51 8.95 633.24 697.41 721.65 PVA_0.75%_C 8.26 8.02 670.90 620.89 743.25 Average 8.34 8.41 636.21 657.91 733.16 S.D 0.15 0.48 33.30 38.32 10.87 PVA C.O.V (%) 1.77 5.73 5.23 5.82 1.48 CELL_0.1%_A 7.55 8.18 645.97 696.18 624.25 CELL_0.1%_B 7.43 7.90 617.56 666.46 635.23 CELL_0.1%_C 7.93 7.46 684.55 637.77 601.75 Average 7.64 7.70 649.36 666.80 620.41 S.D 0.26 0.36 33.62 29.21 17.07 Cell C.O.V (%) 3.42 4.71 5.18 4.38 2.75 ST_1%_A 8.52 9.37 692.58 781.14 765.87 ST_1%_B 8.49 9.30 681.88 804.21 781.35 ST_1%_C 8.47 9.12 669.53 768.88 779.75 Average 8.49 9.26 681.33 784.74 775.66 S.D 0.03 0.13 11.53 17.94 8.51 Steel C.O.V (%) 0.34 1.39 1.69 2.29 1.10 198

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Table G-2. Summary of the values of f'c fst, and fpt obtained for Class V concrete Compressive Strength (ksi) Splitting Tensile Strength (psi) Mix Type Specimen ID Control Fiber Control Fiber Pressure Tension (psi) Control A 9.21 790.41 877.90 Control B 9.88 765.11 938.07 Control C 9.89 788.30 970.97 Average 9.66 781.27 928.98 S.D 0.32 14.04 47.20 PC C.O.V (%) 3.29 N/A 1.80 N/A 5.08 PP_0.5%_A 9.96 9.94 680.45 672.34 PP_0.5%_B 9.73 10.50 656.34 648.51 697.21 PP_0.5%_C 10.24 9.95 675.84 634.61 755.09 Average 9.97 10.13 670.88 651.82 736.15 S.D 0.26 0.32 12.80 19.08 55.07 PP C.O.V (%) 2.56 3.16 1.91 2.93 7.48 PVA_0.75%_A 9.84 10.21 630.34 671.60 PVA_0.75%_B 10.00 9.76 642.12 622.89 756.79 PVA_0.75%_C 9.83 10.32 614.22 651.20 795.57 Average 9.89 10.10 628.89 648.56 776.18 S.D 0.09 0.30 14.01 24.46 27.42 PVA C.O.V (%) 0.93 2.93 2.23 3.77 3.53 CELL_0.1%_A 9.35 8.67 613.61 726.26 606.73 CELL_0.1%_B 9.43 8.97 606.79 708.18 CELL_0.1%_C 9.90 9.86 656.81 731.26 589.89 Average 9.56 9.17 625.74 721.90 633.57 S.D 0.30 0.62 27.13 12.14 11.91 Cell C.O.V (%) 3.10 6.71 4.33 1.68 1.99 ST_1%_A 9.61 10.48 636.54 845.43 757.72 ST_1%_B 9.91 9.91 632.24 762.70 803.71 ST_1%_C 9.77 10.19 593.02 818.31 846.93 Average 9.76 10.19 620.60 808.81 802.79 S.D 0.15 0.28 23.98 42.17 44.61 Steel C.O.V (%) 1.51 2.77 3.86 5.21 5.56 199

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A B C D E Figure G-1. Compression failures for FRC. A) PC. B) PP. C) PVA. D) Cell. E) Steel fiber mixtures. 200

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A B C D E Figure G-2. Splitting tensile failures for FRC. A) PC. B) PP. C) PVA. D) Cell. E) Steel fiber mixtures. 201

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A B C D E Figure G-3. Pressure tensile failures for FRC. A) PC. B) PP. C) PVA. C) Cell. D) Steel fiber mixtures. 202

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APPENDIX H STEEL CORROSION TEST RESULTS -600-500-400-300-200-1000100200060124184244304364424484544604664Exposure Time (days)Potential vs Ti (mV ) -150-100-50050100150200250300Current (Micro Amps ) PC-II-A Potential PC-II-B Potential PC-II-A Current PC-II-B Current Figure H-1. Plain concrete for steel bar corrosion test -600-500-400-300-200-1000100200060124184244304364424484544604664Exposure Time (days)Potential vs Ti (mV ) -150-100-50050100150200250300Current (Micro Amps ) PP-II-A Potential PP-II-B Potential PP-II-A Current PP-II-B Current Figure H-2. Polypropylene fibers for steel bar corrosion test 203

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-600-500-400-300-200-1000100200060124184244304364424484544604664Exposure Time (days)Potential vs Ti (mV ) -150-100-50050100150200250300Current (Micro Amps ) PVA-II-B Potential PVA-II-B Current Figure H-3. Polyvinyl alcohol fibers for steel bar corrosion test -600-500-400-300-200-1000100200060124184244304364424484544604664Exposure Time (days)Potential vs Ti (mV ) -150-100-50050100150200250300Current (Micro Amps ) Cell-II-A Potential Cell-II-B Potentia l Cell-II-A Current Cell-II-B Current Figure H-4. Cellulose fibers for steel bar corrosion test 204

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-600-500-400-300-200-1000100200063123183243303363423483543603Exposure Time (days)Potential vs Ti (mV ) -150-100-50050100150200250300Current (Micro Amps ) Steel-II-A Potential Steel-II-B Potential Steel-II-A Current Steel-II-B Current Figure H-5. Steel fibers for steel bar corrosion test A B Figure H-6. Corroded steel bar for plain concrete mix. A) Specimen A. B) Specimen B. A B Figure H-7. Corroded steel bar for PP fiber mix A) Specimen A. B) Specimen B. 205

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Figure H-8. Steel bar corrosion for PVA fiber mix. A) Specimen B. A B Figure H-9. Steel bar corrosion for cellulose fiber mix. A) Specimen A. B) Specimen B. A B Figure H-10. Steel bar corrosion for steel fiber mix. A) Specimen A. B) Specimen B. 206

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APPENDIX I DEGRADED BEAM TEST RESULTS Table I-1. Averaged UPV test results for Class II concrete Exposure Tank # Tank 1 Tank 6 Tank 9 Tank 3 Tank 7 UPV (m/s) Environmental Exposure Lime-Imm. SaltImm. Swamp-Imm Lime-W/D Salt-W/D PP-II-Precracked 4441 4157 3336 4268 4137 PP-II-Uncracked 4458 4219 3359 4292 4156 PVA-II-Precracked 4561 4306 3468 4355 4133 PVA-II-Uncracked 4599 4357 3528 4355 4262 Steel-II-Precracked 4563 4396 3697 4356 4331 ASTM C 1399 Specimen Steel-II-Uncracked 4639 4375 3715 4349 4344 PC-II-Uncracked 4639 4400 3624 4359 4214 PP-II-Uncracked 4495 4221 3376 4302 4225 PVA-II-Uncracked 4621 4372 3634 4407 4254 ASTM C 1609 Specimen Steel-II-Uncracked 4629 4414 3814 4385 4361 Table I-2. Averaged UPV test results for Class V concrete Exposure Tank # Tank 2 Tank 5 Tank 10 Tank 4 Tank 8 UPV (m/s) Environmental Exposure Lime-Imm. SaltImm. Swamp-Imm Lime-W/D Salt-W/D PP-V-Precracked 4399 4330 3605 4338 4378 PP-V-Uncracked 4572 4351 3676 4355 4457 PVA-V-Precracked 4660 4343 3659 4405 4423 PVA-V-Uncracked 4653 4424 3611 4479 4485 Steel-V-Precracked 4710 4363 3887 4308 4350 ASTM C 1399 Specimen Steel-V-Uncracked 4723 4390 4148 4279 4351 PC-V-Uncracked 4423 4369 3859 4515 4616 PP-V-Uncracked 4578 4316 3823 4449 4476 PVA-V-Uncracked 4695 4426 3621 4562 4520 ASTM C 1609 Specimen Steel-V-Uncracked 4713 4445 4070 4476 4504 207

PAGE 208

208 Table I-3. Summary of the values of residual load and average residual strength obtained for polypropylene fiber mixture for Class II concrete (pre-cracked beam) Residual Load (lbf) Specim PP_I PP_I PP_I A S.D C PP_I PP_I PP_I A S.D C PP_ PP_ PP_ Ave S.D C PP_I PP_I PP_I A S.D C PP_I PP_I PP_I A S.D C en ID 0.02 in 0.03 in 0.04 in 0.05 in Average Residual Strength (psi) I_T1_Lime_Con_Precracked_A 1568 1721 1775 1789 304.95 I_T1_Lime_Con_Precracked_B 1869 2050 2130 2090 363.06I_T1_Lime_Con_Precracked_C 1357 1492 1527 1537 265.07verage 1598 1754 1811 1805 311.03257.31 280.49 303.08 276.86 49.28 .O.V (%) 16.10 15.99 16.74 15.84 15.84 I_T6_Salt_Con_Precracked_A 1558 1663 1740 1754 296.61 I_T6_Salt_Con_Precracked_B 1552 1697 1763 1753 299.56I_T6_Salt_Con_Precracked_C 1322 1432 1495 1545 254.68verage 1477 1597 1666 1684 283.62134.56 144.19 148.54 120.38 25.10 .O.V (%) 9.11 9.03 8.92 7.15 8.85 II_T9_Swamp_Con_Precracked_A 677 746 789 811 143.49 II_T9_Swamp_Con_Precracked_B 530 590 630 658 111.76II_T9_Swamp_Con_Precracked_C 649 714 750 772 136.26rage 619 683 723 747 130.5 78.05 82.40 82.87 79.50 16.63 .O.V (%) 12.62 12.06 11.46 10.64 12.74 I_T3_Lime_WD_Precracked_A 1282 1397 1429 1433 250.25 I_T3_Lime_WD_Precracked_B 1511 1654 1704 1682 298.05I_T3_Lime_WD_Precracked_C 1317 1459 1563 1565 271.32verage 1370 1503 1565 1560 273.21123.36 134.11 137.51 124.58 23.95 .O.V (%) 9.00 8.92 8.79 7.99 8.77 I_T7_Salt_WD_Precracked_A 1330 1425 1405 1390 249.41 I_T7_Salt_WD_Precracked_B 1212 1294 1338 1341 231.86I_T7_Salt_WD_Precracked_C 1407 1488 1507 1468 263.14verage 1316 1402 1416 1399 248.1398.22 98.97 85.10 64.05 15.68 .O.V (%) 7.46 7.06 6.01 4.58 6.32

PAGE 209

209 Table I-4. Continued (un-cracked beam) Residual Load (lbf) Specim PP_I PP_I PP_I A S.D C PP_I PP_I PP_I A S.D C PP_ PP_ PP_ Ave S.D C PP_I PP_I PP_I A S.D C PP_I PP_ PP_ A S.D C *: Cut beam (4 in 3 in in) for IDT. en ID 0.02 in 0.03 in 0.04 in 0.05 in Average Residual Strength (psi) I_T1_Lime_Con_Uncracked_A 1113 1164 1201 1212 297.15 I_T1_Lime_Con_Uncracked_B* 1227 1287 1331 1338 233.49I_T1_Lime_Con_Uncracked_C 1095 1174 1218 1246 212.69verage 1145 1208 1250 1265 247.7871.58 68.31 70.66 65.19 44.00 .O.V (%) 6.25 5.65 5.65 5.15 17.76 I_T6_Salt_Con_Uncracked_A 1153 1216 1252 1253 215.29 I_T6_Salt_Con_Uncracked_B 1163 1209 1246 1260 216.53I_T6_Salt_Con_Uncracked_C 1074 1122 1148 1167 197.80verage 1130 1182 1215 1227 209.8748.75 52.37 58.39 51.79 10.47 .O.V (%) 4.31 4.43 4.80 4.22 4.99 II_T9_Swamp_Con_Uncracked_A 800 836 852 856 152.90 II_T9_Swamp_Con_Uncracked_B 806 870 925 969 161.64II_T9_Swamp_Con_Uncracked_C 662 692 729 753 128.71rage 756 799 835 859 147.7581.46 94.50 99.06 108.04 17.06 .O.V (%) 10.78 11.82 11.86 12.57 11.54 I_T3_Lime_WD_Uncracked_A 1282 1397 1429 1433 250.25 I_T3_Lime_WD_Uncracked_B* 1511 1654 1704 1682 298.05I_T3_Lime_WD_Uncracked_C 1317 1459 1563 1565 271.32verage 1370 1503 1565 1560 273.21123.36 134.11 137.51 124.58 23.95 .O.V (%) 9.00 8.92 8.79 7.99 8.77 I_T7_Salt_WD_Uncracked_A 1042 1078 1070 1084 189.72 II_T7_Salt_WD_Uncracked_B 1387 1442 1466 1473 266.36II_T7_Salt_WD_Uncracked_C 1298 1397 1485 1522 258.17verage 1242 1306 1340 1360 238.09179.11 198.44 234.31 239.99 42.09 .O.V (%) 14.42 15.20 17.48 17.65 17.68

PAGE 210

210 Table I-4. Summary of the valu es of residual load and averag e residual strength obtained for polyvinyl alcohol fiber mi xture for Class II concrete (pre-cracked beam) Residual Load (lbf) Specimen ID 0.02 in 0.03 in 0.04 in 0.05 in Average Residual Strength (psi) PVA_II_T1_Lime_Con_Precracked_A 2440 2580 1906 1301 378.97 PVA_II_T1_Lime_Con_Precracked_B 2150 2340 2040 1463 360.09 PVA_II_T1_Lime_Con_Precracked_C 2160 2130 1933 1397 346.69 Average 2250 2350 1960 1387 361.92 S.D 164.62 225.17 70.87 81.46 16.22 C.O.V (%) 7.32 9.58 3.62 5.87 4.48 PVA_II_T6_Salt_Con_Precracked_A 1519 1644 1592 1241 266.81 PVA_II_T6_Salt_Con_Precracked_B 1646 1781 1794 1590 299.39 PVA_II_T6_Salt_Con_Precracked_C 1635 1614 1557 1157 263.40 Average 1600 1680 1648 1329 276.53 S.D 70.36 89.03 127.93 229.62 19.87 C.O.V (%) 4.40 5.30 7.76 17.27 7.18 PVA_II_T9_Swamp_Con_Precracked_A 546 607 633 654 112.40 PVA_II_T9_Swamp_Con_Precracked_B 478 523 550 574 95.97 PVA_II_T9_Swamp_Con_Precracked_C 540 604 657 704 112.02 Average 521 578 613 644 106.80 S.D 37.65 47.66 56.15 65.57 9.38 C.O.V (%) 7.22 8.24 9.15 10.18 8.78 PVA_II_T3_Lime_WD_Precracked_A 2620 2670 2670 2540 464.01 PVA_II_T3_Lime_WD_Precracked_B 2310 2370 2320 2040 392.63 PVA_II_T3_Lime_WD_Precracked_C 2190 2350 2270 2060 409.64 Average 2373 2463 2420 2213 422.09 S.D 221.89 179.26 217.94 283.08 37.28 C.O.V (%) 9.35 7.28 9.01 12.79 8.83 PVA_II_T7_Salt_WD_Precracked_A 2410 2590 2470 2050 429.96 PVA_II_T7_Salt_WD_Precracked_B 2020 2190 2080 1772 364.09 PVA_II_T7_Salt_WD_Precracked_C 2100 2140 2060 1890 368.96 Average 2177 2307 2203 1904 387.67 S.D 205.99 246.64 231.16 139.53 36.70 C.O.V (%) 9.46 10.69 10.49 7.33 9.47

PAGE 211

211 Table I-4. Continued (un-cracked beam) Residual Load (lbf) Specim PV PV PV A S.D C PVA PVA PVA A S.D C PV PV PV Ave S.D C PV PV PV A S.D C PVA PV PV A S.D C *: Cut beam (4 in 3 in 14 in) for IDT en ID 0.02 in 0.03 in 0.04 in 0.05 in Average Residual Strength (psi) A_II_T1_Lime_Con_Uncracked_A* 1270 1417 1497 1542 365.44 A_II_T1_Lime_Con_Uncracked_B 2480 2750 2580 2130 447.83A_II_T1_Lime_Con_Uncracked_C 1782 2010 2210 2200 371.34verage 1844 2059 2096 1957 394.87607.38 667.85 550.48 361.39 45.96 .O.V (%) 32.94 32.44 26.27 18.46 11.64 _II_T6_Salt_Con_Uncracked_A 1720 1874 1833 1769 318.64 _II_T6_Salt_Con_Uncracked_B 1609 1762 1924 1833 326.74_II_T6_Salt_Con_Uncracked_C 1663 1845 1953 1735 324.17verage 1664 1827 1903 1779 323.1955.51 58.13 62.61 49.76 4.14 .O.V (%) 3.34 3.18 3.29 2.80 1.28 A_II_T9_Swamp_Con_Uncracked_A 647 742 730 670 123.19 A_II_T9_Swamp_Con_Uncracked_B 551 590 628 666 108.62A_II_T9_Swamp_Con_Uncracked_C 588 642 698 750 123.06rage 595 658 685 695 118.2948.42 77.25 52.17 47.38 8.38 .O.V (%) 8.13 11.74 7.61 6.81 7.08 A_II_T3_Lime_WD_Uncracked_A* 907 998 1064 1042 262.00 A_II_T3_Lime_WD_Uncracked_B* 959 995 1036 1074 262.87A_II_T3_Lime_WD_Uncracked_C 1336 1434 1518 1554 265.14verage 1067 1142 1206 1223 263.34234.12 252.60 270.56 286.81 1.62 .O.V (%) 21.94 22.11 22.43 23.45 0.61 _II_T7_Salt_WD_Uncracked_A 1272 1363 1452 1394 243.91 A_II_T7_Salt_WD_Uncracked_B 1935 2110 2180 2240 376.67A_II_T7_Salt_WD_Uncracked_C 1769 1889 1871 1838 331.10verage 1659 1787 1834 1824 317.23345.00 383.74 365.38 423.17 67.46 .O.V (%) 20.80 21.47 19.92 23.20 21.27

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212 Table I-5. Summary of the values of residual load and average residual strength obtained for steel fiber mixture for Class II concrete (pre-cracked beam) Residual Load (lbf) Specim ST_I ST_I ST_I A S.D C ST_I ST_I ST_I A S.D C.O ST_I ST_I ST_I A S.D C ST_I ST_I ST_I A S.D C ST_I ST_I ST_I A S.D C en ID 0.02 in 0.03 in 0.04 in 0.05 in Average Residual Strength (psi) I_T1_Lime_Con_Precracked_A 4890 4440 4100 3660 772.02 I_T1_Lime_Con_Precracked_B 4730 4260 3960 3690 772.29 I_T1_Lime_Con_Precracked_C 4430 4260 4010 3760 762.16 verage 4683 4320 4023 3703 768.82 233.52 103.92 70.95 51.32 5.77 .O.V (%) 4.99 2.41 1.76 1.39 0.75 I_T6_Salt_Con_Precracked_A 4600 4130 3710 3280 724.13 I_T6_Salt_Con_Precracked_B 4950 4400 3960 3590 796.20 I_T6_Salt_Con_Precracked_C 5250 4430 3880 3400 758.43 verage 4933 4320 3850 3423 759.59 325.32 165.23 127.67 156.31 36.05 .V (%) 4600 4130 3710 3280 724.13 I_T9_Swamp_Con_Precracked_A 1848 1864 1827 1789 339.24 I_T9_Swamp_Con_Precracked_B 2300 2210 2120 2060 377.39 I_T9_Swamp_Con_Precracked_C 1812 1698 1642 1571 308.95 verage 1987 1924 1863 1807 341.86 271.95 261.22 241.02 244.98 34.29 .O.V (%) 13.69 13.58 12.94 13.56 10.03 I_T3_Lime_WD_Precracked_A 5490 4740 4450 4170 857.86 I_T3_Lime_WD_Precracked_B 3420 2980 2530 2230 515.44 I_T3_Lime_WD_Precracked_C 3850 3410 3200 3030 638.71 verage 4253 3710 3393 3143 670.67 1092.35 917.55 974.49 974.95 173.43.O.V (%) 25.68 24.73 28.72 31.02 25.86 I_T7_Salt_WD_Precracked_A 3380 3030 2790 2680 544.54 I_T7_Salt_WD_Precracked_B 2560 2490 2220 2070 435.63 I_T7_Salt_WD_Precracked_C 3880 3310 2870 2490 575.24 verage 3273 2943 2627 2413 518.47 666.43 416.81 354.45 312.14 73.36 .O.V (%) 20.36 14.16 13.49 12.93 14.15

PAGE 213

213 Table I-5. Continued (un-cracked beam) Residual Load (lbf) Specim ST_I ST_I ST_I A S.D C ST_I ST_I ST_I A S.D C ST_I ST_I ST_I A S.D 10 C ST_I ST_I ST_I A S.D C ST_I ST_I ST_I A S.D C *: Cut beam (4 in 3 in in) for IDT en ID 0.02 in 0.03 in 0.04 in 0.05 in Average Residual Strength (psi) I_T1_Lime_Con_Uncracked_A* 4360 4120 3670 3380 708.31 I_T1_Lime_Con_Uncracked_B 3930 3790 3530 3210 657.88I_T1_Lime_Con_Uncracked_C 4100 3770 3450 3070 654.80verage 4130 3893 3550 3220 673.66216.56 196.55 111.36 155.24 30.05 .O.V (%) 5.24 5.05 3.14 4.82 4.46 I_T6_Salt_Con_Uncracked_A 4390 4040 3560 3290 679.94 I_T6_Salt_Con_Uncracked_B 4650 4320 3940 3470 725.40I_T6_Salt_Con_Uncracked_C 4010 3700 3480 3090 630.81verage 4350 4020 3660 3283 678.72321.87 310.48 245.76 190.09 47.30 .O.V (%) 7.40 7.72 6.71 5.79 6.97 I_T9_Swamp_Con_Uncracked_A 2200 2220 2180 2040 394.06 I_T9_Swamp_Con_Uncracked_B 2160 2180 2110 1936 383.43I_T9_Swamp_Con_Uncracked_C 2010 2000 1980 1949 366.64verage 2123 2133 2090 1975 381.380.17 117.19 101.49 56.67 13.83 .O.V (%) 4.72 5.49 4.86 2.87 3.63 I_T3_Lime_WD_Uncracked_A 3590 3180 2640 2370 541.31 I_T3_Lime_WD_Uncracked_B 4250 3360 3030 2720 621.62I_T3_Lime_WD_Uncracked_C 4590 3680 3290 3000 675.79verage 4143 3407 2987 2697 612.91508.46 253.25 327.16 315.65 67.66 .O.V (%) 12.27 7.43 10.95 11.71 11.04 I_T7_Salt_WD_Uncracked_A 4250 3260 2740 2440 566.08 I_T7_Salt_WD_Uncracked_B 6320 5110 4000 3380 851.57I_T7_Salt_WD_Uncracked_C 6420 4420 3450 3110 778.12verage 5663 4263 3397 2977 731.921225.00 934.90 631.69 483.98 148.24.O.V (%) 21.63 21.93 18.60 16.26 20.25

PAGE 214

214 Table I-6. Summary of the values of residual load and average residual strength obtained for polypropylene fiber mixture for Class V concrete (pre-cracked beam) Residual Load (lbf) Specim PP_V_ PP_ PP_ A S.D 93 C PP_V_ PP_V_ PP_V_ A S.D C PP_V_ PP_ PP_ Ave S.D C PP_ PP_ PP_V_ A S.D C PP_V_ PP_V_ PP_V_ A S.D C en ID 0.02 in 0.03 in 0.04 in 0.05 in Average Residual Strength (psi) T2_Lime_Con_Precracked_A 1652 1853 1947 1914 341.89 VI_T2_Lime_Con_Precracked_B 1784 1980 2070 2070 351.72V_T2_Lime_Con_Precracked_C verage 1718 1917 2009 1992 346.80 .34 89.80 86.97 110.31 6.95 .O.V (%) 5.43 4.69 4.33 5.54 2.00 T5_Salt_Con_Precracked_A 2110 2290 2360 2320 409.04 T5_Salt_Con_Precracked_B 2110 2300 2420 2440 417.601 T5_Salt_Con_Precracked_C 2100 2280 2380 2410 407.05 verage 2107 2290 2387 2390 411.23 5.77 10.00 30.55 62.45 5.61 .O.V (%) 0.27 0.44 1.28 2.61 1.36 T10_Swamp_Con_Precracked_A 909 1019 1101 1154 189.84 V_T10_Swamp_Con_Precracked_B 690 780 835 859 142.89V_T10_Swamp_Con_Precracked_C 761 840 895 921 158.59rage 787 880 944 978 163.77111.73 124.34 139.52 155.54 23.90 .O.V (%) 14.20 14.13 14.78 15.90 14.60 V_T4_Lime_WD_Precracked_A 939 1030 1085 1115 188.29 V_T4_Lime_WD_Precracked_B 837 909 942 950 163.90T4_Lime_WD_Precracked_C 1293 1408 1422 1431 247.16 verage 1023 1116 1150 1165 199.78 239.32 260.30 246.45 244.42 42.80 .O.V (%) 23.39 23.33 21.44 20.97 21.43 T8_Salt_WD_Precracked_A 2240 2320 2410 2450 395.50 T8_Salt_WD_Precracked_B 1812 1950 2010 2050 330.80 T8_Salt_WD_Precracked_C 1895 2050 2140 2140 348.65 verage 1982 2107 2187 2213 358.32 226.97 191.40 204.04 209.84 33.42 .O.V (%) 11.45 9.09 9.33 9.48 9.33

PAGE 215

215 Table I-6. Continued (un-cracked beam) Residual Load (lbf) Specim PP_V_ PP_V_ PP_V_ A S.D 11 C PP_V_ PP_V_ PP_V_ A S.D 18 C PP_ PP_ PP_ Ave S.D 51 C PP_V_ PP_ PP_ A S.D 32 C PP_V_ PP_ PP_ A S.D 15 C en ID 0.02 in 0.03 in 0.04 in 0.05 in Average Residual Strength (psi) T2_Lime_Con_Uncracked_A 1444 1510 1539 1551 274.30 T2_Lime_Con_Uncracked_B 1232 1320 1361 1356 236.78T2_Lime_Con_Uncracked_C 1267 1350 1380 1368 241.69verage 1314 1393 1427 1425 250.923.65 102.14 97.75 109.28 20.40 .O.V (%) 8.65 7.33 6.85 7.67 8.13 T5_Salt_Con_Uncracked_A 2190 2310 2360 2350 404.85 T5_Salt_Con_Uncracked_B 1824 1958 2030 2050 350.70T5_Salt_Con_Uncracked_C 2090 2220 2270 2290 398.61verage 2035 2163 2220 2230 384.729.17 182.87 170.59 158.75 29.63 .O.V (%) 9.30 8.46 7.68 7.12 7.70 V_T10_Swamp_Con_Uncracked_A 795 853 882 892 157.69 V_T10_Swamp_Con_Uncracked_B 889 949 997 1036 180.57V_T10_Swamp_Con_Uncracked_C 807 868 918 969 162.47rage 830.33 890.00 932.33 965.67 166.91.16 51.64 58.82 72.06 12.07 .O.V (%) 6.16 5.80 6.31 7.46 7.23 T4_Lime_WD_Uncracked_A 1160 1232 1284 1318 228.38 V_T4_Lime_WD_Uncracked_B 997 1057 1088 1110 185.99V_T4_Lime_WD_Uncracked_C 1626 1656 1708 1743 301.83verage 1261 1315 1360 1390 238.736.44 308.00 316.91 322.64 58.61 .O.V (%) 25.89 23.42 23.30 23.21 24.55 T8_Salt_WD_Uncracked_A 1954 1692 1742 1756 314.03 V_T8_Salt_WD_Uncracked_B 1722 1801 1822 1831 309.34V_T8_Salt_WD_Uncracked_C 1653 1754 1791 1790 307.24verage 1776 1749 1785 1792 310.207.68 54.67 40.34 37.55 3.48 .O.V (%) 8.88 3.13 2.26 2.10 1.12

PAGE 216

216 Table I-7. Summary of the valu es of residual load and averag e residual strength obtained for polyvinyl alcohol fiber mi xture for Class V concrete (pre-cracked beam) Residual Load (lbf) Specimen ID 0.02 in 0.03 in 0.04 in 0.05 in Average Residual Strength psi) PVA_V_T2_Lime_Con_Precracked_A 1630 1730 1523 1403 289.56 PVA_V_T2_Lime_Con_Precracked_B 1769 1921 1763 1255 306.72 PVA_V_T2_Lime_Con_Precracked_C 1985 2200 2220 1683 369.80 Average 1795 1950 1835 1447 322.03 S.D 178.89 236.37 354.09 217.37 42.26 C.O.V (%) 9.97 12.12 19.29 15.02 13.12 PVA_V_T5_Salt_Con_Precracked_A 1639 1760 1536 1321 279.76 PVA_V_T5_Salt_Con_Precracked_B 2310 2390 1960 1578 355.98 PVA_V_T5_Salt_Con_Precracked_C 2350 2660 2500 1694 391.97 Average 2100 2270 1999 1531 342.57 S.D 399.45 461.84 483.16 190.89 57.30 C.O.V (%) 19.02 20.35 24.17 12.47 16.73 PVA_V_T10_Swamp_Con_Precracked_A 1116 1258 1365 1452 233.86 PVA_V_T10_Swamp_Con_Precracked_B 1044 1154 1211 1131 207.07 PVA_V_T10_Swamp_Con_Precracked_C 1173 1293 1389 1439 243.26 Average 1111 1235 1322 1341 228.06 S.D 64.65 72.30 96.59 181.69 18.78 C.O.V (%) 5.82 5.85 7.31 13.55 8.23 PVA_V_T4_Lime_WD_Precracked_A 1760 1924 1990 1927 341.57 PVA_V_T4_Lime_WD_Precracked_B 1917 2080 2070 2080 370.66 PVA_V_T4_Lime_WD_Precracked_C 1682 1796 1851 1648 315.09 Average 1786 1933 1970 1885 342.44 S.D 119.69 142.23 110.82 219.04 27.80 C.O.V (%) 6.70 7.36 5.62 11.62 8.12 PVA_V_T8_Salt_WD_Precracked_A 1914 1995 1861 1594 336.73 PVA_V_T8_Salt_WD_Precracked_B 1938 2160 2090 1567 353.75 PVA_V_T8_Salt_WD_Precracked_C 2190 2310 2140 1949 382.19 Average 2014 2155 2030 1703 357.56 S.D 152.89 157.56 148.76 213.18 22.97 C.O.V (%) 7.59 7.31 7.33 12.52 6.42

PAGE 217

217 Table I-7. Continued (un-cracked beam) Residual Load (lbf) Specimen ID 0.02 in 0.03 in 0.04 in 0.05 in Average Residual Strength (psi) PVA_V_T2_Lime_Con_Uncracked_A 1096 1212 1259 1216 224.22 PVA_V_T2_Lime_Con_Uncracked_B 1628 1739 1705 1355 300.52 PVA_V_T2_Lime_Con_Uncracked_C 1340 1423 1537 1491 273.50 Average 1355 1458 1500 1354 266.08 S.D 266.30 265.24 225.25 137.50 38.69 C.O.V (%) 19.66 18.19 15.01 10.16 14.54 PVA_V_T5_Salt_Con_Uncracked_A 1498 1694 1717 1752 300.83 PVA_V_T5_Salt_Con_Uncracked_B 1733 1906 1894 1813 335.91 PVA_V_T5_Salt_Con_Uncracked_C 1795 1977 2010 1927 348.20 Average 1675 1859 1874 1831 328.31 S.D 156.67 147.24 147.55 88.83 24.58 C.O.V (%) 9.35 7.92 7.88 4.85 7.49 PVA_V_T10_Swamp_Con_Uncracked_A 860 989 1093 1160 190.38 PVA_V_T10_Swamp_Con_Uncracked_B 828 913 989 1071 174.25 PVA_V_T10_Swamp_Con_Uncracked_C 923 997 1066 1124 193.63 Average 870.33 966.33 1049.33 1118.33 186.09 S.D 48.34 46.36 53.97 44.77 10.38 C.O.V (%) 5.55 4.80 5.14 4.00 5.58 PVA_V_T4_Lime_WD_Uncracked_A 1682 1746 1835 1761 328.50 PVA_V_T4_Lime_WD_Uncracked_B 1923 2040 2120 1994 384.35 PVA_V_T4_Lime_WD_Uncracked_C 1437 1518 1598 1567 289.06 Average 1681 1768 1851 1774 333.97 S.D 243.00 261.69 261.37 213.80 47.88 C.O.V (%) 14.46 14.80 14.12 12.05 14.34 PVA_V_T8_Salt_WD_Uncracked_A 1663 1781 1835 1746 323.63 PVA_V_T8_Salt_WD_Uncracked_B 1775 1958 2120 2140 363.71 PVA_V_T8_Salt_WD_Uncracked_C 1531 1618 1722 1585 298.14 Average 1656 1786 1892 1824 328.49 S.D 122.14 170.05 205.10 285.54 33.06 C.O.V (%) 7.37 9.52 10.84 15.66 10.06

PAGE 218

218 Table I-8. Summary of the valu es of residual load and averag e residual strength obtained for steel fiber mixture for Class V concrete (pre-cracked beam) Residual Load (lbf) Specimen ID 0.02 in 0.03 in 0.04 in 0.05 in Average Residual Strength (psi) ST_V_T2_Lime_Con_Precracked_A 5660 5270 5010 4700 925.39 ST_V_T2_Lime_Con_Precracked_B 4740 4530 4290 4160 786.57 ST_V_T2_Lime_Con_Precracked_C 5300 4790 4400 4120 828.12 Average 5233 4863 4567 4327 846.69 S.D 463.61 375.41 387.86 323.93 71.25 C.O.V (%) 8.86 7.72 8.49 7.49 8.42 ST_V_T5_Salt_Con_Precracked_A 4730 4530 4120 3810 766.80 ST_V_T5_Salt_Con_Precracked_B 5220 4720 4380 4150 821.89 ST_V_T5_Salt_Con_Precracked_C 4960 4630 4130 3850 766.66 Average 4970 4627 4210 3937 785.12 S.D 245.15 95.04 147.31 185.83 31.84 C.O.V (%) 4.93 2.05 3.50 4.72 4.06 ST_V_T10_Swamp_Con_Precracked_A 2050 2050 2020 1961 376.92 ST_V_T10_Swamp_Con_Precracked_B 2450 2360 2250 2060 414.00 ST_V_T10_Swamp_Con_Precracked_C 1948 1866 1783 1662 331.90 Average 2149 2092 2018 1894 374.28 S.D 265.33 249.66 233.51 207.21 41.12 C.O.V (%) 12.34 11.93 11.57 10.94 10.99 ST_V_T4_Lime_WD_Precracked_A 4530 3970 3470 2960 692.91 ST_V_T4_Lime_WD_Precracked_B 4380 3470 3040 2590 613.30 ST_V_T4_Lime_WD_Precracked_C 4670 3900 3490 2980 689.39 Average 4527 3780 3333 2843 665.20 S.D 145.03 270.74 254.23 219.62 44.98 C.O.V (%) 3.20 7.16 7.63 7.72 6.76 ST_V_T8_Salt_WD_Precracked_A 4130 3850 3350 3130 641.94 ST_V_T8_Salt_WD_Precracked_B 4380 3720 3120 2830 636.09 ST_V_T8_Salt_WD_Precracked_C 4310 3470 3190 2850 628.77 Average 4273 3680 3220 2937 635.60 S.D 128.97 193.13 117.90 167.73 6.60 C.O.V (%) 3.02 5.25 3.66 5.71 1.04

PAGE 219

219 Table I-8. Continued (un-cracked beam) Residual Load (lbf) Specimen ID 0.02 in 0.03 in 0.04 in 0.05 in Average Residual Strength (psi) ST_V_T2_Lime_Con_Uncracked_A 5050 4970 4770 4570 894.09 ST_V_T2_Lime_Con_Uncracked_B 5570 5180 4430 4130 891.86 ST_V_T2_Lime_Con_Uncracked_C 4010 3820 3720 3580 695.26 Average 4877 4657 4307 4093 827.07 S.D 794.31 732.14 535.75 496.02 114.16 C.O.V (%) 16.29 15.72 12.44 12.12 13.80 ST_V_T5_Salt_Con_Uncracked_A 4940 4780 4610 4360 839.90 ST_V_T5_Salt_Con_Uncracked_B 5450 5050 4450 4010 852.13 ST_V_T5_Salt_Con_Uncracked_C 4320 4080 3860 3640 725.19 Average 4903 4637 4307 4003 805.74 S.D 565.89 500.63 395.01 360.05 70.03 C.O.V (%) 11.54 10.80 9.17 8.99 8.69 ST_V_T10_Swamp_Con_Uncracked_A 3140 3130 3090 3050 556.35 ST_V_T10_Swamp_Con_Uncracked_B 3100 3080 3010 2950 540.20 ST_V_T10_Swamp_Con_Uncracked_C 3260 3280 3230 3080 586.08 Average 3167 3163 3110 3027 560.88 S.D 83.27 104.08 111.36 68.07 23.27 C.O.V (%) 2.63 3.29 3.58 2.25 4.15 ST_V_T4_Lime_WD_Uncracked_A 5210 4110 3380 2680 719.16 ST_V_T4_Lime_WD_Uncracked_B 4660 3930 3070 2760 651.22 ST_V_T4_Lime_WD_Uncracked_C 5170 3950 3100 2480 672.14 Average 5013 3997 3183 2640 680.84 S.D 306.65 98.66 170.98 144.22 34.80 C.O.V (%) 6.12 2.47 5.37 5.46 5.11 ST_V_T8_Salt_WD_Uncracked_A 5000 3230 2210 1672 552.42 ST_V_T8_Salt_WD_Uncracked_B 4920 3720 2620 1134 561.10 ST_V_T8_Salt_WD_Uncracked_C 4600 3820 3110 2630 650.74 Average 4840 3590 2647 1812 588.09 S.D 211.66 315.75 450.59 757.76 54.43 C.O.V (%) 4.37 8.80 17.02 41.82 9.26

PAGE 220

220Table I-9. Summary of the values of pe rformance of FRC obtained for polypropylene fi ber mixture for Class II concrete (un-cracked beam) Experimental Test Parameter Calculations for ASTM C 1609-06 Specimen ID P1(lbf) PP(lbf) f1(psi) fP(psi) 1(in) P( in) P4,0.02(lbf) f4,0.02(psi) P4,0.08(lbf) F4,0.08 (psi) T4, 0.08 (in-lbf) PP_II_T1_Lime_Con_Uncracked_A 5260 5260 972 972 2.29E-03 2.29E-03 1953 361 2050 379 190 PP_II_T1_Lime_Con_Uncracked_B 5100 5100 947 947 2.26E-03 2.26E-03 2440 453 2480 460 221 PP_II_T1_Lime_Con_Uncracked_C 5190 5190 968 968 2.13E-03 2.13E-03 1683 314 1825 341 173 Average 5183 5183 962 962 2.23E-03 2.23E-03 2025 376 2118 393 195 S.D 80.21 80.21 13.43 13.43 8.79E-05 8.79E-05 383.65 70.74 332.80 61.28 24.50 C.O.V (%) 1.55 1.55 1.40 1.40 3.95 3.95 18.94 18.82 15.71 15.58 12.59 PP_II_T6_Salt_Con_Uncracked_A 5110 5110 923 923 2.49E-03 2.49E-03 1378 249 1378 249 145 PP_II_T6_Salt_Con_Uncracked_B 5100 5100 915 915 2.85E-03 2.85E-03 1178 211 1317 236 141 PP_II_T6_Salt_Con_Uncracked_C 4890 4890 881 881 2.67E-03 2.67E-03 1297 234 1350 243 143 Average 5033 5033 906 906 2.67E-03 2.67E-03 1284 231 1348 243 143 S.D 124.23 124.23 22.13 22.13 1.78E-04 1.78E-04 100.06 18.97 30.53 6.40 2.09 C.O.V (%) 2.47 2.47 2.44 2.44 6.66 6.66 7.83 8.20 2.26 2.64 1.46 PP_II_T9_Swamp_Con_Uncracked_A 1771 1771 331 331 2.39E-03 2.39E-03 764 143 904 169 75 PP_II_T9_Swamp_Con_Uncracked_B 2090 2090 388 388 2.80E-03 2.80E-03 749 139 836 155 75 PP_II_T9_Swamp_Con_Uncracked_C 1937 1937 356 356 2.64E-03 2.64E-03 766 141 845 155 73 Average 1933 1933 358 358 2.61E-03 2.61E-03 760 141 862 160 74 S.D 159.54 159.54 28.82 28.82 2.07E-04 2.07E-04 9.29 1.76 36.94 7.76 1.04 C.O.V (%) 8.26 8.26 8.04 8.04 7.93 7.93 1.22 1.25 4.29 4.86 1.39

PAGE 221

221Table I-9. Continued (un-cracked beam) Experimental Test Parameter Calculations for ASTM C 1609-06 Specim en ID P1(lbf) PP(lbf) f1(psi) fP(psi) 1(in) P( in) P4,0.02(lbf) f4,0.02(psi) P4,0.08(lbf) F4,0.08 (psi) T4, 0.08 (in-lbf) PP_II_T3_Lime_WD_Uncracked_A 5240 5240 935 935 1.99E-03 1.99E-03 1520 271 1609 287 158 PP_II_T3_Lime_WD_Uncracked_B 5220 5220 913 913 2.15E-03 2.15E-03 1130 198 1301 228 133 PP_II_T3_Lime_WD_Uncracked_C 5450 5450 956 956 2.20E-03 2.20E-03 1376 241 1464 257 148 Average 5303 5303 935 935 2.11E-03 2.11E-03 1342 237 1458 257 147 S.D 127.41 127.41 21.35 21.35 1.07E-04 1.07E-04 197.21 36.97 154.09 29.73 12.59 C.O.V (%) 2.40 2.40 2.28 2.28 5.08 5.08 14.70 15.61 10.57 11.56 8.59 PP_II_T7_Salt_WD_Uncracked_A 5070 5070 944 944 1.76E-03 1.76E-03 1799 335 1950 363 179 PP_II_T7_Salt_WD_Uncracked_B 5440 5440 1010 1010 1.88E-03 1.88E-03 1837 341 1820 338 175 PP_II_T7_Salt_WD_Uncracked_C 5060 5060 949 949 2.08E-03 2.08E-03 1821 341 2080 390 183 Average 5190 5190 967 967 1.90E-03 1.90E-03 1819 339 1950 364 179 S.D 216.56 216.56 36.86 36.86 1.59E-04 1.59E-04 19.08 3.71 130.00 26.08 4.39 C.O.V (%) 4.17 4.17 3.81 3.81 8.35 8.35 1.05 1.09 6.67 7.17 2.45

PAGE 222

222Table I-10. Summary of the values of performance of FRC obtained for polyvinyl alcohol fiber mixture for Class II concrete (un cracked beam) Experimental Test Parameter Calculations for ASTM C 1609-06 Specimen ID P1(lbf) PP(lbf) f1(psi) fP(psi) 1(in) P( in) P4,0.02(lbf) f4,0.02(psi) P4,0.08(lbf) F4,0.08 (psi) T4, 0.08 (in-lbf) PVA_II_T1_Lime_Con_Uncracked_A 5360 5360 978 978 2.46E-03 2.46E-03 2100 383 1370 250 193 PVA_II_T1_Lime_Con_Uncracked_B 4850 4850 872 872 2.15E-03 2.15E-03 2150 387 1356 244 186 PVA_II_T1_Lime_Con_Uncracked_C 4870 4870 895 895 1.99E-03 1.99E-03 2130 391 1562 287 196 Average 5027 5027 915 915 2.20E-03 2.20E-03 2127 387 1429 260 192 S.D 288.85 288.85 55.79 55.79 2.38E-04 2.38E-04 25.17 4.17 115.11 23.41 5.32 C.O.V (%) 5.75 5.75 6.10 6.10 10.83 10.83 1.18 1.08 8.05 8.99 2.78 PVA_II_T6_Salt_Con_Uncracked_A 5210 5210 965 965 2.87E-03 2.87E-03 2200 407 912 169 178 PVA_II_T6_Salt_Con_Uncracked_B 5160 5160 934 934 2.70E-03 2.70E-03 2410 436 1764 319 203 PVA_II_T6_Salt_Con_Uncracked_C 5570 5570 994 994 2.84E-03 2.84E-03 1836 328 1052 188 172 Average 5313 5313 964 964 2.80E-03 2.80E-03 2149 390 1243 225 184 S.D 223.68 223.68 29.75 29.75 9.18E-05 9.18E-05 290.42 56.34 456.88 82.03 16.49 C.O.V (%) 4.21 4.21 3.09 3.09 3.28 3.28 13.52 14.43 36.77 36.40 8.95 PVA_II_T9_Swamp_Con_Uncracked_A 2200 2200 394 394 3.11E-03 3.11E-03 866 155 982 176 86 PVA_II_T9_Swamp_Con_Uncracked_B 2430 2430 441 441 5.13E-03 5.13E-03 899 163 899 163 92 PVA_II_T9_Swamp_Con_Uncracked_C 2050 2050 374 374 2.86E-03 2.86E-03 879 160 1031 188 88 Average 2227 2227 403 403 3.70E-03 3.70E-03 881 159 971 176 89 S.D 191.40 191.40 34.54 34.54 1.25E-03 1.25E-03 16.62 4.22 66.73 12.45 3.06 C.O.V (%) 8.60 8.60 8.57 8.57 33.69 33.69 1.89 2.65 6.87 7.09 3.43

PAGE 223

223Table I-10. Continued (un-cracked beam) Experimental Test Parameter Calculations for ASTM C 1609-06 Specimen ID P1(lbf) PP(lbf) f1(psi) fP(psi) 1(in) P( in) P4,0.02(lbf) f4,0.02(psi) P4,0.08(lbf) F4,0.08 (psi) T4, 0.08 (in-lbf) PVA_II_T3_Lime_WD_Uncracked_A 5200 5200 985 985 1.92E-03 1.92E-03 1516 287 1673 317 164 PVA_II_T3_Lime_WD_Uncracked_B 5890 5890 1075 1075 1.90E-03 1.90E-03 1743 318 1559 284 184 PVA_II_T3_Lime_WD_Uncracked_C 5980 5980 1091 1091 1.95E-03 1.95E-03 1997 367 1515 276 197 Average 5690 5690 1050 1050 1.92E-03 1.92E-03 1752 324 1582 293 181 S.D 426.73 426.73 57.16 57.16 2.20E-05 2.05E-05 240.63 40.31 81.54 21.42 16.59 C.O.V (%) 7.50 7.50 5.44 5.44 1.14 1.07 13.73 12.44 5.15 7.32 9.14 PVA_II_T7_Salt_WD_Uncracked_A 6130 6130 1105 1105 1.98E-03 1.98E-03 1844 332 1090 196 177 PVA_II_T7_Salt_WD_Uncracked_B 6100 6100 1113 1113 2.05E-03 2.05E-03 1635 298 868 158 164 PVA_II_T7_Salt_WD_Uncracked_C 6040 6040 1097 1097 2.09E-03 2.09E-03 1956 355 1653 300 201 Average 6090 6090 1105 1105 2.04E-03 2.04E-03 1812 329 1204 218 181 S.D 45.83 45.83 8.18 8.18 5.94E-05 5.94E-05 162.92 28.59 404.66 73.35 18.56 C.O.V (%) 0.75 0.75 0.74 0.74 2.91 2.91 8.99 8.70 33.62 33.60 10.27

PAGE 224

224Table I-11. Summary of the values of performance of FRC obtained for steel fiber mixture for Class II concrete (un-cracked beam) Experimental Test Parameter Calculations for ASTM C 1609-06 Specim en ID P1(lbf) PP(lbf) f1(psi) fP(psi) 1(in) P( in) P4,0.02(lbf) f4,0.02(psi) P4,0.08(lbf) F4,0.08 (psi) T4, 0.08 (in-lbf) ST_II_T1_Lime_Con_Uncracked_A 6490 6740 1187 1233 2.80E-03 1.08E-02 6330 1158 3980 728 426 ST_II_T1_Lime_Con_Uncracked_B 5600 5870 1024 1074 2.44E-03 7.46E-03 5220 955 3070 562 347 ST_II_T1_Lime_Con_Uncracked_C 5790 5790 1064 1064 2.34E-03 4860 893 2600 478 317 Average 5960 1092 1124 2.52E-03 5470 1002 3217 589 363 S.D 468.72 84.80 94.64 2.45E-04 766.22 138.35 701.59 127.26 56.46 C.O.V (%) 7.86 7.77 8.42 9.70 14.01 13.81 21.81 21.60 15.54 ST_II_T6_Salt_Con_Uncracked_A 5730 5730 1030 1030 2.80E-03 2.80E-03 3790 681 2480 446 263 ST_II_T6_Salt_Con_Uncracked_B 6070 6070 1099 1099 2.96E-03 2.96E-03 4530 820 2330 422 295 ST_II_T6_Salt_Con_Uncracked_C 5910 5910 1052 1052 2.97E-03 2.97E-03 3890 693 2070 375 263 Average 5903 5903 1061 1061 2.91E-03 2.91E-03 4070 731 2293 414 274 S.D 170.10 170.10 35.26 35.26 9.25E-05 9.25E-05 401.50 77.20 207.44 36.13 18.28 C.O.V (%) 2.88 2.88 3.32 3.32 3.18 3.18 9.86 10.55 9.05 8.72 6.68 ST_II_T9_Swamp_Con_Uncracked_A 2710 2710 501 501 3.77E-03 3.77E-03 2720 502 2289 423 181 ST_II_T9_Swamp_Con_Uncracked_B 2690 2690 487 487 3.31E-03 3.31E-03 2350 426 1797 325 174 ST_II_T9_Swamp_Con_Uncracked_C 2390 2390 443 443 3.64E-03 3.64E-03 2240 415 2050 380 172 Average 2597 2597 477 477 3.57E-03 3.57E-03 2437 448 2045 376 175 S.D 179.26 179.26 30.35 30.35 2.37E-04 2.37E-04 251.46 47.80 246.03 48.81 4.70 C.O.V (%) 6.90 6.90 6.37 6.37 6.64 6.64 10.32 10.68 12.03 12.98 2.68

PAGE 225

225Table I-11. Continued (un-cracked beam) Experimental Test Parameter Calculations for ASTM C 1609-06 Specimen ID P1(lbf) PP(lbf) f1(psi) fP(psi) 1(in) P( in) P4,0.02(lbf) f4,0.02(psi) P4,0.08(lbf) F4,0.08 (psi) T4, 0.08 (in-lbf) ST_II_T3_Lime_WD_Uncracked_A 6450 6451 1177 1177 2.16E-03 2.16E-03 4100 748 1816 331 255 ST_II_T3_Lime_WD_Uncracked_B 6020 6020 1088 1088 2.18E-03 2.18E-03 4520 817 2190 396 282 ST_II_T3_Lime_WD_Uncracked_C 5890 5890 1064 1064 2.36E-03 2.36E-03 4670 854 1975 357 285 Average 6120 6120 1109 1110 2.23E-03 2.23E-03 4430 806 1994 361 274 S.D 293.09 293.65 59.53 59.63 1.07E-04 1.07E-04 295.47 53.88 187.70 32.37 16.47 C.O.V (%) 4.79 4.80 5.37 5.37 4.81 4.81 6.67 6.68 9.41 8.96 6.02 ST_II_T7_Salt_WD_Uncracked_A 6750 6750 1238 1238 2.28E-03 2.28E-03 4410 809 1599 293 251 ST_II_T7_Salt_WD_Uncracked_B 6750 6750 1244 1244 2.37E-03 2.37E-03 5210 960 2600 479 327 ST_II_T7_Salt_WD_Uncracked_C 6760 6760 1221 1221 2.21E-03 2.21E-03 4660 842 2640 477 317 Average 6753 6753 1234 1234 2.28E-03 2.28E-03 4760 870 2280 416 298 S.D 5.77 5.77 11.69 11.69 8.02E-05 8.02E-05 409.27 79.60 589.81 106.71 41.61 C.O.V (%) 0.09 0.09 0.95 0.95 3.52 3.52 8.60 9.15 25.87 25.63 13.94

PAGE 226

226Table I-12. Summary of the values of performance of FRC obtained for polypropyl ene fiber mixture for Cl ass V concrete (un-crac ked beam) Experimental Test Parameter Calculations for ASTM C 1609-06 Specimen ID P1(lbf) PP(lbf) f1(psi) fP(psi) 1(in) P( in) P4,0.02(lbf) f4,0.02(psi) P4,0.08(lbf) F4,0.08 (psi) T4, 0.08 (in-lbf) PP_V_T2_Lime_Con_Uncracked_A 5840 5840 1065 1065 2.07E-03 2.07E-03 1675 306 1694 309 182 PP_V_T2_Lime_Con_Uncracked_B 5950 5950 1083 1083 1.99E-03 1.99E-03 1559 284 1635 298 175 PP_V_T2_Lime_Con_Uncracked_C 6020 6020 1090 1090 2.03E-03 2.03E-03 1735 314 1688 306 175 Average 5937 5937 1079 1079 2.03E-03 2.03E-03 1656 301 1672 304 177 S.D 90.74 90.74 12.69 12.69 3.98E-05 3.98E-05 89.47 15.71 32.47 5.91 3.82 C.O.V (%) 1.53 1.53 1.18 1.18 1.96 1.96 5.40 5.22 1.94 1.94 2.15 PP_V_T5_Salt_Con_Uncracked_A 7210 7210 1277 1277 2.84E-03 2.84E-03 1691 300 1852 328 202 PP_V_T5_Salt_Con_Uncracked_B 7300 7300 1303 1303 2.81E-03 2.81E-03 1853 331 223 PP_V_T5_Salt_Con_Uncracked_C 7150 7150 1251 1251 2.81E-03 2.81E-03 1413 247 204 Average 7220 7220 1277 1277 2.82E-03 2.82E-03 1691 300 1706 302 210 S.D 75.50 75.50 25.65 25.65 1.61E-05 1.61E-05 253.75 47.40 11.28 C.O.V (%) 1.05 1.05 2.01 2.01 0.57 0.57 14.87 15.69 5.38 PP_V_T10_Swamp_Con_Uncracked_A 2890 2890 538 538 2.97E-03 2.97E-03 885 165 1155 215 95 PP_V_T10_Swamp_Con_Uncracked_B 2860 2860 507 507 2.60E-03 2.30E-03 783 139 1012 179 93 PP_V_T10_Swamp_Con_Uncracked_C 2380 2380 440 440 2.79E-03 2.79E-03 951 176 1166 215 94 Average 2710 2710 495 495 2.79E-03 2.69E-03 873 160 1111 203 94 S.D 286.18 286.18 50.21 50.21 1.85E-04 3.47E-04 84.64 18.99 85.91 20.74 0.88 C.O.V (%) 10.56 10.56 10.15 10.15 6.64 12.91 9.70 11.89 7.73 10.21 0.94

PAGE 227

227Table I-12. Continued (un-cracked beam) Experimental Test Parameter Calculations for ASTM C 1609-06 Specim en ID P1(lbf) PP(lbf) f1(psi) fP(psi) 1(in) P( in) P4,0.02(lbf) f4,0.02(psi) P4,0.08(lbf) F4,0.08 (psi) T4, 0.08 (in-lbf) PP_V_T4_Lime_WD_Uncracked_A 6450 6450 1222 1222 2.18E-03 2.18E-03 1776 336 198 PP_V_T4_Lime_WD_Uncracked_B 6290 6290 1177 1177 2.10E-03 2.10E-03 2090 391 2200 412 216 PP_V_T4_Lime_WD_Uncracked_C 6190 6190 1170 1170 2.09E-03 2.09E-03 2150 406 2320 438 217 Average 6310 6310 1189 1189 2.12E-03 2.12E-03 2120 399 2099 395 210 S.D 131.15 131.15 28.36 28.36 5.22E-05 5.22E-05 42.43 10.79 285.81 52.83 10.25 C.O.V (%) 2.08 2.08 2.38 2.38 2.46 2.46 2.00 2.71 13.62 13.36 4.87 PP_V_T8_Salt_WD_Uncracked_A 6880 6880 1216 1216 2.02E-03 2.02E-03 1597 282 196 PP_V_T8_Salt_WD_Uncracked_B 7370 7370 1302 1302 2.21E-03 2.21E-03 1494 264 192 PP_V_T8_Salt_WD_Uncracked_C 6830 6830 1222 1222 2.06E-03 2.06E-03 2080 372 222 Average 7027 7027 1247 1247 2.10E-03 2.10E-03 1724 306 203 S.D 298.38 298.38 48.21 48.21 1.00E-04 1.00E-04 312.86 57.90 16.56 C.O.V (%) 4.25 4.25 3.87 3.87 4.78 4.78 18.15 18.91 8.15

PAGE 228

228Table I-13. Summary of the values of performance of FRC obtained for polyvinyl alcohol fiber mixture for Class V concrete (uncracked beam) Experimental Test Parameter Calculations for ASTM C 1609-06 Specimen ID P1(lbf) PP(lbf) f1(psi) fP(psi) 1(in) P( in) P4,0.02(lbf) f4,0.02(psi) P4,0.08(lbf) F4,0.08 (psi) T4, 0.08 (in-lbf) PVA_V_T2_Lime_Con_Uncracked_A 5610 5610 979 979 1.93E-03 1.93E-03 1199 209 977 171 151 PVA_V_T2_Lime_Con_Uncracked_B 5620 5620 971 971 1.86E-03 1.86E-03 1255 217 1028 178 150 PVA_V_T2_Lime_Con_Uncracked_C 5660 5660 978 978 2.18E-03 2.18E-03 1234 213 833 144 149 Average 5630 5630 976 976 1.99E-03 1.99E-03 1229 213 946 164 150 S.D 26.46 26.46 4.26 4.26 1.68E-04 1.68E-04 28.29 3.83 101.13 17.76 1.24 C.O.V (%) 0.47 0.47 0.44 0.44 8.46 8.46 2.30 1.80 10.69 10.82 0.82 PVA_V_T5_Salt_Con_Uncracked_A 7190 7190 1268 1268 2.82E-03 2.82E-03 1761 310 1283 226 214 PVA_V_T5_Salt_Con_Uncracked_B 7310 7310 1289 1289 2.65E-03 2.65E-03 1730 305 1323 233 207 PVA_V_T5_Salt_Con_Uncracked_C 7230 7230 1259 1259 2.68E-03 2.68E-03 1889 329 1370 239 212 Average 7243 7243 1272 1272 2.71E-03 2.71E-03 1793 315 1325 233 211 S.D 61.10 61.10 15.24 15.24 8.89E-05 8.89E-05 84.29 12.56 43.55 6.21 3.54 C.O.V (%) 0.84 0.84 1.20 1.20 3.28 3.28 4.70 3.99 3.29 2.67 1.68 PVA_V_T10_Swamp_Con_Uncracked_A 2450 2450 447 447 3.22E-03 3.22E-03 1054 192 1220 223 109 PVA_V_T10_Swamp_Con_Uncracked_B 2640 1640 480 298 2.74E-03 2.74E-03 1195 217 1336 243 119 PVA_V_T10_Swamp_Con_Uncracked_C 2450 2450 444 444 2.34E-03 2.34E-03 1031 185 1033 187 104 Average 2513 2180 457 396 2.77E-03 2.77E-03 1093 198 1196 218 111 S.D 109.70 467.65 20.36 84.80 4.41E-04 4.41E-04 88.79 17.10 152.88 28.37 7.48 C.O.V (%) 4.36 21.45 4.45 21.39 15.94 15.94 8.12 8.62 12.78 13.04 6.74

PAGE 229

229Table I-13. Continued (un-cracked beam) Experimental Test Parameter Calculations for ASTM C 1609-06 Specimen ID P1(lbf) PP(lbf) f1(psi) fP(psi) 1(in) P( in) P4,0.02(lbf) f4,0.02(psi) P4,0.08(lbf) F4,0.08 (psi) T4, 0.08 (in-lbf) PVA_V_T4_Lime_WD_Uncracked_A 6690 6690 1233 1233 2.06E-03 2.06E-03 3400 627 1368 252 204 PVA_V_T4_Lime_WD_Uncracked_B 6690 6690 1221 1221 2.04E-03 2.40E-03 1552 283 1080 197 183 PVA_V_T4_Lime_WD_Uncracked_C 7190 7190 1302 1302 2.12E-03 2.12E-03 1568 282 1171 212 191 Average 6857 6857 1252 1252 2.07E-03 2.19E-03 2173 397 1206 220 193 S.D 288.68 288.68 44.05 44.05 3.86E-05 1.86E-04 1062.35 198.60 147.22 28.45 10.69 C.O.V (%) 4.21 4.21 3.52 3.52 1.86 8.49 48.88 50.00 12.20 12.91 5.55 PVA_V_T8_Salt_WD_Uncracked_A 7770 7770 1383 1383 2.33E-03 2.33E-03 1340 239 217 PVA_V_T8_Salt_WD_Uncracked_B 6960 6960 1279 1279 2.19E-03 2.19E-03 1519 279 196 PVA_V_T8_Salt_WD_Uncracked_C 7890 7890 1418 1418 2.45E-03 2.45E-03 2260 406 1875 337 251 Average 7540 7540 1360 1360 2.32E-03 2.32E-03 2260 406 1578 285 221 S.D 505.87 505.87 72.29 72.29 1.30E-04 1.30E-04 272.34 49.51 27.90 C.O.V (%) 6.71 6.71 5.31 5.31 5.60 5.60 17.26 17.38 12.61

PAGE 230

230Table I-14. Summary of the values of performance of FRC obtained for steel fiber mixture for Class V concrete (un-cracked beam) Experimental Test Parameter Calculations for ASTM C 1609-06 Specim en ID P1(lbf) PP(lbf) f1(psi) fP(psi) 1(in) P( in) P4,0.02(lbf) f4,0.02(psi) P4,0.08(lbf) F4,0.08 (psi) T4, 0.08 (in-lbf) ST_V_T2_Lime_Con_Uncracked_A 6320 6410 1114 1130 2.30E-03 1.08E-02 5730 1010 3900 687 402 ST_V_T2_Lime_Con_Uncracked_B 6690 6690 1145 1145 2.40E-03 2.40E-03 5880 1007 4440 760 427 ST_V_T2_Lime_Con_Uncracked_C 6340 6340 1148 1148 2.09E-03 2.09E-03 5020 927 3290 596 345 Average 6450 1136 1141 2.26E-03 5543 981 3877 681 392 S.D 208.09 18.96 9.86 1.60E-04 459.38 46.69 575.35 82.26 41.84 C.O.V (%) 3.23 1.67 0.86 7.10 8.29 4.76 14.84 12.08 10.69 ST_V_T5_Salt_Con_Uncracked_A 7260 7260 1289 1042 2.90E-03 2.90E-03 5470 971 3490 620 374 ST_V_T5_Salt_Con_Uncracked_B 7680 7680 1370 1126 2.88E-03 2.88E-03 6050 1079 3600 642 403 ST_V_T5_Salt_Con_Uncracked_C 7250 7250 1297 1023 3.00E-03 3.00E-03 5270 943 3700 662 377 Average 7397 7397 1319 1064 2.93E-03 2.93E-03 5597 998 3597 641 385 S.D 245.42 245.42 44.85 54.64 6.43E-05 6.43E-05 405.13 72.18 105.04 21.10 16.28 C.O.V (%) 3.32 3.32 3.40 5.14 2.20 2.20 7.24 7.23 2.92 3.29 4.23 ST_V_T10_Swamp_Con_Uncracked_A 2920 2920 550 499 2.61E-03 2.61E-03 2310 435 2310 435 199 ST_V_T10_Swamp_Con_Uncracked_B 3410 3410 619 481 3.20E-03 3.20E-03 2640 479 2220 403 197 ST_V_T10_Swamp_Con_Uncracked_C 3200 3200 597 565 2.94E-03 2.94E-03 3020 563 2480 463 219 Average 3177 3177 589 515 2.91E-03 2.91E-03 2657 493 2337 434 205 S.D 245.83 245.83 35.13 44.30 2.96E-04 2.96E-04 355.29 65.11 132.04 29.87 12.10 C.O.V (%) 7.74 7.74 5.97 8.60 10.16 10.16 13.37 13.22 5.65 6.89 5.89

PAGE 231

231Table I-14. Continued (un-cracked beam) Experimental Test Parameter Calculations for ASTM C 1609-06 Specimen ID P1(lbf) PP(lbf) f1(psi) fP(psi) 1(in) P( in) P4,0.02(lbf) f4,0.02(psi) P4,0.08(lbf) F4,0.08 (psi) T4, 0.08 (in-lbf) ST_V_T4_Lime_WD_Uncracked_A 6970 6970 1268 1196 2.05E-03 2.05E-03 4630 843 1516 276 265 ST_V_T4_Lime_WD_Uncracked_B 6830 6830 1237 1237 2.01E-03 2.01E-03 3630 657 1310 237 215 ST_V_T4_Lime_WD_Uncracked_C 6770 6770 1229 1187 2.21E-03 2.21E-03 4980 904 1281 233 263 Average 6857 6857 1245 1207 2.09E-03 2.09E-03 4413 801 1369 249 248 S.D 102.63 102.63 20.88 26.56 1.03E-04 1.03E-04 700.59 128.41 128.13 23.79 28.06 C.O.V (%) 1.50 1.50 1.68 2.20 4.92 4.92 15.87 16.02 9.36 9.57 11.32 ST_V_T8_Salt_WD_Uncracked_A 7470 7570 1307 1325 2.29E-03 1.10E-02 7360 1288 2870 502 403 ST_V_T8_Salt_WD_Uncracked_B 7570 8250 1341 1461 2.23E-03 9.15E-03 7660 1357 2850 505 426 ST_V_T8_Salt_WD_Uncracked_C 6860 7240 1274 1344 2.03E-03 1.04E-02 6720 1173 3390 629 430 Average 7300 7687 1307 1377 2.18E-03 1.02E-02 7247 1272 3037 545 419 S.D 384.32 515.01 33.64 73.93 1.37E-04 9.64E-04 480.14 92.87 306.16 72.67 14.75 C.O.V (%) 5.26 6.70 2.57 5.37 6.26 9.45 6.63 7.30 10.08 13.32 3.52

PAGE 232

01000200030004000500060007000800090000.000.010.020.030.040.050.06Deflection (in)Reload (lbf) PP-II-Limewater-Immersion-Precracked PP-II-Saltwater-Immersion-Precracked PP-II-Swampwater-Immersion-Precracked PP-II-Limewater-WD-Precracked PP-II-Saltwater-WD-Precracked A 01000200030004000500060007000800090000.000.010.020.030.040.050.06Deflection (in)Reload (lbf) PP-II-Limewater-Immersion-Uncracked PP-II-Saltwater-Immersion-Uncracked PP-II-Swampwater-Immersion-Uncracked PP-II-Limewater-WD-Uncracked PP-II-Saltwater-WD-Uncracked B Figure I-1. Residual load vs. deflection curve for PP fiber mix for Class II concrete. A) Pre-cracked beams. B) Un-cracked beams. 232

PAGE 233

01000200030004000500060007000800090000.000.010.020.030.040.050.06Deflection (in)Reload (lbf) PP-V-Limewater-Immersion-Precracked PP-V-Saltwater-Immersion-Precracked PP-V-Swampwater-Immersion-Precracked PP-V-Limewater-WD-Precracked PP-V-Saltwater-WD-Precracked A 01000200030004000500060007000800090000.000.010.020.030.040.050.06Deflection (in)Reload (lbf) PP-V-Limewater-Immersion-Uncracked PP-V-Saltwater-Immersion-Uncracked PP-V-Swampwater-Immersion-Uncracked PP-V-Limewater-WD-Uncracked PP-V-Saltwater-WD-Uncracked B Figure I-2. Residual load vs. deflection curve for PP fiber mix for Class V concrete. A) Pre-cracked beams. B) Un-cracked beams. 233

PAGE 234

01000200030004000500060007000800090000.000.010.020.030.040.050.06Deflection (in)Reload (lbf) PVA-II-Limewater-Immersion-Precracked PVA-II-Saltwater-Immersion-Precracked PVA-II-Swampwater-Immersion-Precracked PVA-II-Limewater-WD-Precracked PVA-II-Saltwater-WD-Precracked A 01000200030004000500060007000800090000.000.010.020.030.040.050.06Deflection (in)Reload (lbf) PVA-II-Limewater-Immersion-Uncracked PVA-II-Saltwater-Immersion-Uncracked PVA-II-Swampwater-Immersion-Uncracked PVA-II-Limewater-WD-Uncracked PVA-II-Saltwater-WD-Uncracked B Figure I-3. Residual load vs. deflection curve for PVA fiber mix for Class II concrete. A) Pre-cracked beams. B) Un-cracked beams. 234

PAGE 235

01000200030004000500060007000800090000.000.010.020.030.040.050.06Deflection (in)Reload (lbf) PVA-V-Limewater-Immersion-Precracked PVA-V-Saltwater-Immersion-Precracked PVA-V-Swampwater-Immersion-Precracked PVA-V-Limewater-WD-Precracked PVA-V-Saltwater-WD-Precracked A 01000200030004000500060007000800090000.000.010.020.030.040.050.06Deflection (in)Reload (lbf) PVA-V-Limewater-Immersion-Uncracked PVA-V-Saltwater-Immersion-Uncracked PVA-V-Swampwater-Immersion-Uncracked PVA-V-Limewater-WD-Uncracked PVA-V-Saltwater-WD-Uncracked B Figure I-4. Residual load vs. deflection curve for PVA fiber mix for Class V concrete. A) Pre-cracked beams. B) Un-cracked beams. 235

PAGE 236

01000200030004000500060007000800090000.000.010.020.030.040.050.06Deflection (in)Reload (lbf) Steel-II-Limewater-Immersion-Precracked Steel-II-Saltwater-Immersion-Precracked Steel-II-Swampwater-Immersion-Precracked Steel-II-Limewater-WD-Precracked Steel-II-Saltwater-WD-Precracked A 01000200030004000500060007000800090000.000.010.020.030.040.050.06Deflection (in)Reload (lbf) Steel-II-Limewater-Immersion-Uncracked Steel-II-Saltwater-Immersion-Uncracked Steel-II-Swampwater-Immersion-Uncracked Steel-II-Limewater-WD-Uncracked Steel-II-Saltwater-WD-Uncracked B Figure I-5. Residual load vs. deflection curve for steel fiber mix for Class II concrete. A) Pre-cracked beams. B) Un-cracked beams. 236

PAGE 237

01000200030004000500060007000800090000.000.010.020.030.040.050.06Deflection (in)Reload (lbf) Steel-V-Limewater-Immersion-Precracked Steel-V-Saltwater-Immersion-Precracked Steel-V-Swampwater-Immersion-Precracked Steel-V-Limewater-WD-Precracked Steel-V-Saltwater-WD-Precracked A 01000200030004000500060007000800090000.000.010.020.030.040.050.06Deflection (in)Reload (lbf) Steel-V-Limewater-Immersion-Uncracked Steel-V-Saltwater-Immersion-Uncracked Steel-V-Swampwater-Immersion-Uncracked Steel-V-Limewater-WD-Uncracked Steel-V-Saltwater-WD-Uncracked B Figure I-6. Residual load vs. deflection curve for steel fiber mix for Class V concrete. A) Pre-cracked beams. B) Un-cracked beams. 237

PAGE 238

01000200030004000500060007000800090000.0000.0010.0020.0030.0040.0050.0060.0070.008Deflection (in)Load (lbf ) PC-II-Limewater-Immersion PC-II-Saltwater-Immersion PC-II-Swampwater-Immersion PC-II-Limewater-WD PC-II-Saltwater-WD A 01000200030004000500060007000800090000.0000.0010.0020.0030.0040.0050.0060.0070.008Deflection (in)Load (lbf ) PC-V-Limewater-Immersion PC-V-Saltwater-Immersion PC-V-Swampwater-Immersion PC-V-Limewater-WD PC-V-Saltwater-WD B Figure I-7. Load vs. deflection curve for plain concrete mixes. A) Class II. B) Class V. 238

PAGE 239

01000200030004000500060007000800090000.000.010.020.030.040.050.060.070.08Deflection (in)Load (lbf ) PP-II-Limewater-Immersion PP-II-Saltwater-Immersion PP-II-Swampwater-Immersion PP-II-Limewater-WD PP-II-Saltwater-WD A 01000200030004000500060007000800090000.000.010.020.030.040.050.060.070.08Deflection (in)Load (lbf ) PP-V-Limewater-Immersion PP-V-Saltwater-Immersion PP-V-Swampwater-Immersion PP-V-Limewater-WD PP-V-Saltwater-WD B Figure I-8. Load vs. deflection curve for PP fiber mixes. A) Class II. B) Class V. 239

PAGE 240

01000200030004000500060007000800090000.000.010.020.030.040.050.060.070.08Deflection (in)Load (lbf ) PVA-II-Limewater-Immersion PVA-II-Saltwater-Immersion PVA-II-Swampwater-Immersion PVA-II-Limewater-WD PVA-II-Saltwater-WD A 01000200030004000500060007000800090000.000.010.020.030.040.050.060.070.08Deflection (in)Load (lbf ) PVA-V-Limewater-Immersion PVA-V-Saltwater-Immersion PVA-V-Swampwater-Immersion PVA-V-Limewater-WD PVA-V-Saltwater-WD B Figure I-9. Load vs. deflection curve for PVA fiber mixes. A) Class II. B) Class V 240

PAGE 241

241 0 1000 2000 3000 4000 5000 6000 7000 8000 9000 0.0000.0010.0020.0030.0040.005 Deflection (in)Load (lbf ) Cell-II-Limewater-Immersion Cell-II-Saltwater-Immersion Cell-II-Swampwater-Immersion Cell-II-Limewater-WD Cell-II-Saltwater-WD A 0 1000 2000 3000 4000 5000 6000 7000 8000 9000 0.0000.0010.0020.0030.0040.005 Deflection (in)Load (lbf ) Cell-V-Limewater-Immersion Cell-V-Saltwater-Immersion Cell-V-Swampwater-Immersion Cell-V-Limewater-WD Cell-V-Saltwater-WD B Figure I-10. Load vs. deflection curve for cellulose fi ber mixes. A) Class II. B) Class V.

PAGE 242

242 0 1000 2000 3000 4000 5000 6000 7000 8000 9000 0.000.010.020.030.040.050.060.070.08 Deflection (in)Load (lbf ) ST-II-Limewater-Immersion ST-II-Saltwater-Immersion ST-II-Swampwater-Immersion ST-II-Limewater-WD ST-II-Saltwater-WD A 0 1000 2000 3000 4000 5000 6000 7000 8000 9000 0.000.010.020.030.040.050.060.070.08 Deflection (in)Load (lbf ) ST-V-Limewater-Immersion ST-V-Saltwater-Immersion ST-V-Swampwater-Immersion ST-V-Limewater-WD ST-V-Saltwater-WD B Figure I-11. Load vs. deflection curve for st eel fiber mixes. A) Class II. B) Class V.

PAGE 243

243 APPENDIX J INDIRECT TENSILE TEST RESULTS y = 0.0004x + 1 R2 = 0.9294 y = 0.0009x + 1 R2 = 0.9871 y = 0.248x + 1 R2 = 0.9368 y = 0.0327x + 1 R2 = 0.9661 0 1 2 3 4 5 6 7 050100150200250300350400450500 No. of CyclesResilient Deformation Ratio ST-II-Limewater Immersion ST-II-Saltwater Immersion Figure J-1. Fiber bridging zone for st eel fiber mix for Class II concrete y = 0.0808x + 1 R2 = 0.9711 y = 0.444x + 1 R2 = 0.916 y = 0.0313x + 1 R2 = 0.8259 y = 0.0403x + 1 R2 = 0.9948 0 1 2 3 4 5 6 7 020406080100 No. of CyclesResilient Deformation Ratio ST-II-Limewater W/D ST-II-Saltwater W/D Figure J-1. Continued

PAGE 244

244 y = 0.0145x + 1 R2 = 0.9659 y = 0.0099x + 1 R2 = 0.9129 y = 0.0203x + 1 R2 = 0.8708 y = 0.0264x + 1 R2 = 0.9943 0 1 2 3 4 5 6 7 0100200300400500 No. of CyclesResilient Deformation Ratio PP-II-Limewater Immersion PP-II-Saltwater Immersion Figure J-2. Fiber bridging zone for PP fiber mix for Class II concrete y = 0.0903x + 1 R2 = 0.8423 y = 0.086x + 1 R2 = 0.76 y = 0.1648x + 1 R2 = 0.9488 y = 0.0093x + 1 R2 = 0.8737 y = 0.0109x + 1 R2 = 0.9961 y = 0.005x + 1 R2 = 0.9784 0 1 2 3 4 5 6 7 0100200300400500 No. of CyclesResilient Deformation Ratio PP-II-Limewater W/D PP-II-Saltwater W/D Figure J-2. Continued

PAGE 245

245 y = 0.0011x + 1 R2 = 0.6615 y = 0.0007x + 1 R2 = 0.7255 y = 0.0006x + 1 R2 = 0.7078 y = 0.2535x + 1 R2 = 0.9156 y = 0.9451x + 1 R2 = 0.7502 0 1 2 3 4 5 6 7 0100200300400500 No. of CyclesResilient Deformation Ratio PVA-II-Limewater Immersion PVA-II-Saltwater Immersion Figure J-3. Fiber bridging zone for PVA fiber mix for Class II concrete y = 0.0064x + 1 R2 = 0.9597 y = 0.0027x + 1 R2 = 0.8296 y = 0.1154x + 1 R2 = 0.9214 y = 0.2666x + 1 R2 = 0.932 y = 0.0247x + 1 R2 = 0.7833 0 1 2 3 4 5 6 7 0100200300400500 No. of CyclesResilient Deformation Ratio PVA-II-Limewater W/D PVA-II-Saltwater W/D Figure J-3. Continued

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246 LIST OF REFERENCES ACI Committee 544 (1999), “Measurement of Prope rties of Fiber-Reinforced Concrete,” ACI 544.2R-99. ACI Committee 544 (1996), “Sta te-of-the-Art Report on Fiber-R einforced Concrete,” ACI 544.1R-96. ASHTO-AGC-ARTBA Joint Committee (2001), “The Use and State-of-the -Practice of Fiber Reinforced Concrete,” American Concrete Pavement Association ASTM C 39/C 39M-01 (2004), “Standard Test Met hod for Compressive Strength of Cylindrical Concrete Specimen,” Annual Book of ASTM Standards. ASTM C 78 (2004), “Standard Test Method for Flexural Strength of Concrete (Using Simple Beam with Third-Point Loading),” Annual Book of ASTM Standards. ASTM C 94/C 94M (2004), “Standard Specifica tion for Ready-Mixed Concrte” Annual Book of ASTM Standards. ASTM C 143/C 143M-00 (2004), “Standard Test Method for Slump of Hydraulic-Cement Concrete,” Annual Book of ASTM Standards. ASTM C 192/C 192 M-02 (2004),” Standard Practice for Making and Curing Concrete Test Specimens in the Laboratory,” Annual Book of ASTM Standards. ASTM C 231-97 (2004), “Standard Test Method fo r Air Content of Freshly Mixed Concrete by the Pressure Method,” Annual Book of ASTM Standards. ASTM C 496-01 (2004), “Standard Test Method fo r Splitting Tensile Strength of Cylindrical Concrete Specimen,” Annual Book of ASTM Standards, 2004. ASTM C 597-02 (2004), “Standard Test Method fo r Pulse Velocity Through Concrete,” Annual Book of ASTM Standards. ASTM C 642-97 (2004), “Standard Test Met hod for Density, Absorption, and Voids in Hardened Concrete,” Annual Book of ASTM Standards. ASTM C 995-94 (2004), “Standard Test Method for Time of Flow of Fibe r-Reinforced Concrete through Inverted Slump Cone,” Annual Book of ASTM Standards. ASTM C 1116-03 (2004), “Standard Specificat ion for Fiber-Reinforced Concrete and Shortcrete,” Annual Book of ASTM Standards. ASTM C 1018-97 (2004), “Standard Test Met hod for Flexural Toughness and First-Crack Strength of Fiber-Reinforced C oncrete (Using Beam with Th ird-Point Loading),” Annual Book of ASTM Standards.

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247 ASTM C1170-91 (2004), “Standard Test Method for Determini ng Consistency and Density of Roller-Compacted Concrete Usi ng a Vibrating Table,” Annual Book of ASTM Standards. ASTM C 1399-07a (2008), “Standard Test Method for Obtaining Average Residual-Strength of Fiber-Reinforced Concrete,” A nnual Book of ASTM Standards. ASTM C 1585-04e1 (2004), “Standard Test Method for Measurment of Rate of Absorption of Water by Hydraulic-Cement Concretes. ” Annual Book of ASTM Standards. ASTM C 1609-06 (2008), “Standard Test Method for Flexural Pe rformance of Fiber-Reinforced Concrete (Using Beam with Third-Point Lo ading),” Annual Book of ASTM Standards. ASTM G109-99a (2004),”Standard Test Method for Determina tion the Effects of Chemical Admixtures on the Corrosion of Embedded Stee l Reinforcement in Concrete Exposed to Chloride Environments,” Annual Book of ASTM Standards. Al-Tayyib, A.J., Al-Zahrani, M. M., Rasheeduzzafar and Al-Suaim ani, G.J. (1988), “Effect of Polypropylene Fiber Reinforcement on the Propert ies of Fresh and Harden Concrete in the Arabian Gulf Environment,” Cement and Concrete Research Vol. 18, pp. 561-570. Al-Khalaf, M.N. and Page, C.L. (1979), “Steel Mortar Interfaces: Micros tructural Features and Mode of Failure,” Cement and Concrete Research Vol. 9, pp. 197-208. Balaguru PN, Ramakrishnan V. (1986), “Freeze-Thaw Durability of Fiber Reinforced Concrete,” ACI Journal (May-June), Vol. 83, pp. 374-382. Banthia, N. & Trottier, J.F. (Jan.-Feb. 1995), “Test Methods for Flexural Toughness Characterization of Fiber Re inforced Concrete: Some C oncerns and a Proposition,” ACI Materials Journal Vol 92, pp. 48-57. Beaudoin, J.J. (1990), Handbook of Fiber-Reinforced Conc rete: Principles, Properties, Developments and Applications Noyes Publications, Inc., New Jersey. Bentur, A. & Mindess, S. (1990), Fibre Reinforced Cementitious Composites Elsevier Applied Science, London and New York. Bentur, A, Mindess, S, Vondran, G. (1989), “Bonding in Polypropylene Fibre Reinforced Concretes,” The International Journal of Cement Composite and Lightweight Concrete Vol 11, No. 3. Bertolini,L., Elsener, B., Pede ferri, and Polder, R.B. (2004), Corrosion of Steel in Concrete WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Buckeye UltraFiber500PTM PFiber A/E Manual (2006), Buckeye Technologies Inc. Bungey, J. H. (1989), Testing of Concrete in Structures 2PndP edition, Chapman and Hall, p.52.

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253 BIOGRAPHICAL SKETCH Byoungil Kim was born in Gyeongsan, Republic of Korea, to Duekkwon Kim and Yeungok Song. He received a Bachelor of Engineeri ng degree in architectural engineering from Yeungnam University in February 2003 and then ma rried on October. He got scholarship from Korea Science & Engineering F oundation (KOSEF) and decided to come across the Pacific to have more advanced experience in United State. In fall 2004 he joined the Master program in Ci vil Engineering at the University of Florida and worked as a graduate research assistant firs tly with Dr. Andrew J. Boyd. After two years, in 2006, he earned his Master of Engineering degree and then continued his Ph.D program with Dr. Reynaldo Roque. He completed the Doctor of Philosophy degree in civil engineering at the University of Florida in August 2009. After completing his Ph.D., he plans to work in academia, government agencies, or private companies in Civil or Architectural Engineerin g to continue his service to the community.