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Implementation of Highly Reactive Pozzolans in the Key Royale Bridge Replacement

Permanent Link: http://ufdc.ufl.edu/UFE0022792/00001

Material Information

Title: Implementation of Highly Reactive Pozzolans in the Key Royale Bridge Replacement
Physical Description: 1 online resource (99 p.)
Language: english
Creator: Tsai, Yen-Chih
Publisher: University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: 2008

Subjects

Subjects / Keywords: capacity, capwap, corrosion, durability, edc, pda, piles, potentials, pozzolans
Civil and Coastal Engineering -- Dissertations, Academic -- UF
Genre: Civil Engineering thesis, M.S.
bibliography   ( marcgt )
theses   ( marcgt )
government publication (state, provincial, terriorial, dependent)   ( marcgt )
born-digital   ( sobekcm )
Electronic Thesis or Dissertation

Notes

Abstract: The Florida Department of Transportation (FDOT) recently completed construction on a small concrete bridge constructed with precast, pretensioned piles located in a coastal environment. Six different concrete mixtures were used to construct the piling. They contained fly ash, ultra-fine fly ash, ground granulated blast furnace slag, metakaolin, and silica fume. The sixth mixture was a Portland cement only control with no supplementary cementitious materials used. Funding was provided for this work from the Federal Highway Administration Innovative Bridge Research and Construction Program, which helps state, county and local bridge owners incorporate innovative materials and materials technologies in their bridge projects. The focus of the project is to investigate the long-term durability of the piles constructed with these new materials when in a marine environment. This paper covers the design, construction and early monitoring of the piles. The second objective of this project is to evaluate the new pile driving monitoring system, Embedded Data Collector (EDC). Reduced strain and acceleration, pile stresses, and pile capacities collected using EDC were compared to the data collected from using the conventional monitoring system, Pile Driving Analyzer (PDA).
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 Yen-Chih Tsai.
Thesis: Thesis (M.S.)--University of Florida, 2008.
Local: Adviser: Hamilton, Homer R.

Record Information

Source Institution: UFRGP
Rights Management: Applicable rights reserved.
Classification: lcc - LD1780 2008
System ID: UFE0022792:00001

Permanent Link: http://ufdc.ufl.edu/UFE0022792/00001

Material Information

Title: Implementation of Highly Reactive Pozzolans in the Key Royale Bridge Replacement
Physical Description: 1 online resource (99 p.)
Language: english
Creator: Tsai, Yen-Chih
Publisher: University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: 2008

Subjects

Subjects / Keywords: capacity, capwap, corrosion, durability, edc, pda, piles, potentials, pozzolans
Civil and Coastal Engineering -- Dissertations, Academic -- UF
Genre: Civil Engineering thesis, M.S.
bibliography   ( marcgt )
theses   ( marcgt )
government publication (state, provincial, terriorial, dependent)   ( marcgt )
born-digital   ( sobekcm )
Electronic Thesis or Dissertation

Notes

Abstract: The Florida Department of Transportation (FDOT) recently completed construction on a small concrete bridge constructed with precast, pretensioned piles located in a coastal environment. Six different concrete mixtures were used to construct the piling. They contained fly ash, ultra-fine fly ash, ground granulated blast furnace slag, metakaolin, and silica fume. The sixth mixture was a Portland cement only control with no supplementary cementitious materials used. Funding was provided for this work from the Federal Highway Administration Innovative Bridge Research and Construction Program, which helps state, county and local bridge owners incorporate innovative materials and materials technologies in their bridge projects. The focus of the project is to investigate the long-term durability of the piles constructed with these new materials when in a marine environment. This paper covers the design, construction and early monitoring of the piles. The second objective of this project is to evaluate the new pile driving monitoring system, Embedded Data Collector (EDC). Reduced strain and acceleration, pile stresses, and pile capacities collected using EDC were compared to the data collected from using the conventional monitoring system, Pile Driving Analyzer (PDA).
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 Yen-Chih Tsai.
Thesis: Thesis (M.S.)--University of Florida, 2008.
Local: Adviser: Hamilton, Homer R.

Record Information

Source Institution: UFRGP
Rights Management: Applicable rights reserved.
Classification: lcc - LD1780 2008
System ID: UFE0022792:00001


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1 IMPLEMENTATION OF HIGHLY REACTIVE POZZOLANS IN THE KEY ROYALE BRIDGE REPLACEMENT By YEN CHIH TSAI A THESIS PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLOR IDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE UNIVERSITY OF FLORIDA 2008

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2 2008 Yen Chih Tsai

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3 To my loving family, my mother Ching Hua Ha n; my brother Yen Chun Tsai; my uncle, Buo Kou Han; my aunt, Trina Han; and my girlfriend, Autumn Chim as they have offered their unyielding love and support

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4 ACKNOWLEDGMENTS I would like to express my gr atitude to the Federal Highw ay Adm inistration Innovative Bridge Research and Construction Program for c ontributing funding for this project. I would also like to acknowledge Cone and Graham, Dura-Stre ss Inc., Smart Structures Inc., and all the SCM suppliers, Civil & Marine, Boral, Grace, and Burgess, for their time and effort to make this research successful. I would like to thank my advisor, Dr. Tr ey Hamilton, for his continuous support and guidance. I truly appreciate his knowledge on the subject and valuab le time to make this project successful. It is my honor to be one of his graduate students. I would like to also acknowledge Dr. Michael McVay from Univ ersity of Florida, Rodrigo Herrera from Florida Department of Transportation, and Chris Freyman from Smart Structures Inc. for their knowledge, assistances, and valuable time on the subject of evaluation of driven piles. I would like to thank Ivan Lasa, Mario Pa redes, Dennis Baldi, Mathew Duncan and Richard Delorenzo from the Florida Department of Transportation for their assistance and knowledge on taking corrosion reading and laboratory testing. I w ould also like to acknowledge the graduate students, undergradu ate students, and faculty from th e University of Florida for the contribution of their time and knowledge in the laboratory and on the field. They include Chuck Broward, Robert Gomez, Gustavo Llanos, Edward Roske, Stefan Szyniszewski, and Enrique Vivas. Finally, I thank Dr. Gary Consolazio a nd Dr. Michael McVay for serving on my supervisory committee and their in sight and willingness to help.

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5 TABLE OF CONTENTS page UACKNOWLEDGMENTS ...............................................................................................................4ULIST OF TABLES ...........................................................................................................................7ULIST OF FIGURES .........................................................................................................................9UABSTRACT ...................................................................................................................................12 CHAP TER 1 UINTRODUCTION ..................................................................................................................132 USTRUCTURE DESCRIPTION ..............................................................................................143 UCONCRETE MIXTURE DESIGNS ......................................................................................174 UPILE DESIGN AND CONSTRUCTION ...............................................................................20UDesign .....................................................................................................................................20UPile Production and Material Sampling ..................................................................................21UCuring, Prestress Transfer, and Transportation ......................................................................21USampling .................................................................................................................................225 UPILE INSTRUMENTATION .................................................................................................35UOverview .................................................................................................................................35UCorrosion Sensors ...................................................................................................................35UEmbedded Data Collector .......................................................................................................36UCovermeter .............................................................................................................................376 UDURABILITY SEGMENT ....................................................................................................41UOverview .................................................................................................................................41UDesign and Construction .........................................................................................................41UCorrosion Instrumentation ......................................................................................................42UTemperature Instrumentation ..................................................................................................437 UPILE DRIVING ......................................................................................................................48UMethod of Installation .............................................................................................................48UMonitoring Pile Driving with PDA ........................................................................................49UMonitoring Pile Driving with EDC ........................................................................................52UComparison of PDA and EDC Results ...................................................................................54UComparison of Measured Force, A cceleration, and Particle Velocity ...................................55UComparison of Driving Stress and Pile Capacity ...................................................................57

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6 UCAPWAP Analysis of PDA Data ...........................................................................................58UAnalysis of Skin Friction and End Bearing Resistances ........................................................618 UCORROSION MONITORING ..............................................................................................80UCorrosion Potential of Prestressing Strands, Steel, and Titanium Electrodes ........................80USurface Resistivity ..................................................................................................................84UElectrical Resistance of Steel and Titanium Electrodes .........................................................85UElectrical Current of Steel Electrodes .....................................................................................859 USUMMARY AND CONCLUSIONS .....................................................................................96ULIST OF REFERENCES ...............................................................................................................98UBIOGRAPHICAL SKETCH .........................................................................................................99

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7 LIST OF TABLES Table page 3-1 Notation used to denote 6 mixt ures used in bridge piles ................................................... 193-2 Mixture designs selected for use in CEM, UFA, and FA piles ..........................................193-3 Mixture designs selected for use in SF, MET, and BFS piles ........................................... 194-1 Pile casting schedule ..................................................................................................... .....264-2 Summary of number and types of samples taken from each mixture (F 18fender pile) ......................................................................................................................... ...........264-3 Summary of number and types of samples taken from each mixture (24bridge pile) ..... 264-4 Summary of types of sample used in each test .................................................................. 274-5 Summary of mechanical prope rties (a) (F 18fender pile) ................................................ 274-6 Summary of mechanical prope rties (b) (F 18fender pile) ................................................ 274-7 Summary of mechanical pr operties (24bridge pile) ......................................................... 274-8 Summary of durability prope rties (a) (F 18fender pile) ...................................................284-9 Summary of durability prope rties (b) (F 18fender pile) ................................................... 284-10 Summary of durability pr operties (24bridge pile) ........................................................... 284-11 Modulus of rupture, compressive st rength, and coefficient at 28 days ............................. 287-1 All the invalid piles with its malfunctioned EDC parts .....................................................647-2 Summary table of PDA/EDC stresses and capacity ratio ..................................................647-3 Descriptions of labels .........................................................................................................647-4 Summary table of FDOT pile database ..............................................................................647-5 Comparison of EDC and CAPWAP skin, tip, and total resist ances in kips ......................657-6 Summary table of CAPWAP /EDC static tip, skin, a nd total resistance ratio .................... 657-7 Summary table of FDOT pile database ..............................................................................658-1 Location of corrosion electrodes in 24-in FA and UFA piles ............................................ 86

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8 8-2 Location of corrosion electrodes in 24-in SF, BFS, and MET piles .................................. 868-3 A dimension for surface resistivity and external potential measurements ..................... 868-4 External electrodes measuring locations ............................................................................ 868-5 Pile casting schedule ..................................................................................................... .....86

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9 LIST OF FIGURES Figure page U2-1 Key Royale Drive Bridge was selected for this project .....................................................16 U2-2 Bridge foundation plan showing bridge and fender pile layout .........................................16 U4-1 Spiral ties spacing for 18-in & 24-in piles .........................................................................29 U4-2 Cross section of square piles. A) 24-in. B) 18-in ...............................................................29 U4-3 18-in fender pile with prsstressed strands been pulled ......................................................29 U4-4 Pile casting at precast yard .................................................................................................30 U4-5 Lifting loop were stabbed into the concrete after screeding ..............................................30 U4-6 Moist curing at precast yard ...............................................................................................31 U4-7 An epoxy was applied to th e area for corrosion protection ...............................................31 U4-8 Molded cylinders and beams were used to sample the concrete from each representative mixture ........................................................................................................32 U4-9 Sample segment with debonded strands from which cores were ta ken. A) Side view. B) Top view .......................................................................................................................32 U4-10 Compressive strength of all mixtures at 28, 91, and 365 days ..........................................33 U4-11 Surface resistivity of all mixtures at 28, 91, and 365 days ................................................33 U4-12 RMT of all mixtures at 56 and 365 days ............................................................................34 U5-1 Location of corrosion sensors and EDC ............................................................................38 U5-2 A) #3 steel electrode with 2-in length of the electrode exposed. B) 3-in titanium electrode with 2-in lengt h of the electrode exposed ..........................................................38 U5-3 Wired corrosion sensors (top-titanium, bottom-steel) .......................................................39 U5-4 Smart sensors and corrosion probes on the right ...............................................................39 U5-5 Battery and radio transmitter are included for wireless data transmission ........................40 U5-6 Cross-Sectional View of 24 pile with strand nomenclature and layout ...........................40 U6-1 Durability segment after installation on the fender pile .....................................................44

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10 U6-2 Durability segments were attached to the fender piles ......................................................44 U6-3 Durability segment and sample segment construction .......................................................45 U6-4 Sample segment and durability se gment were divided by a plywood sheet ......................45 U6-5 Sample segment and durability segments after concrete been poured ..............................46 U6-6 Repair of durability segment. A) Before repair. B) After repair .......................................46 U6-7 Instrumentation in the durability segment .........................................................................47 U6-8 Thermocouples grip system ...............................................................................................47 U7-1 Pile installation for piles in bents 3 and 4 ..........................................................................66 U7-2 Pile Driving Analyzer (P DA) computer that analyzes and displays the driving data ........66 U7-3 Strain gauges and accelerometers were m ounted to surface of the pile at pile top ...........67 U7-4 One-dimensional wave propagation ..................................................................................67 U7-5 SmartPile Review analyzes and displays the drive data ....................................................68 U7-6 Measured force between EDC and P DA for bent 3 pile BFS at blow #280 ......................68 U7-7 Measured acceleration between EDC a nd PDA for bent 3 pile BFS at blow #280 ...........69 U7-8 Calculated particle velocity between ED C and PDA for bent 3 pile BFS at blow #280 ...69 U7-9 Case method pile capacity between EDC and PDA with Jc of 0.3 for bent 3 pile BFS ....70 U7-10 Maximum compressive stress at the top of pile between EDC and PDA for bent 3 pile BFS .............................................................................................................................70 U7-11 Maximum tensile stress at the top of pile between EDC and PDA for bent 3 pile BFS ....71 U7-12 Page 1 of the CAPWAP analysis table output for bent 3 pile FA blow #166 ...................72 U7-13 Page 2 of the CAPWAP analysis table output for bent 3 pile FA blow #166 ...................73 U7-14 Page 3 of the CAPWAP analysis tabl e output for Bent 3 Pile FA blow #166 ..................74 U7-15 Plotted output of CAPWAP anal ysis for Bent 3 Pile FA blow #166 .................................75 U7-16 Relationship between the predicted CA PWAP skin capacity and EDC skin capacity ......76 U7-17 Relationship between the predicted CAPWAP tip capacity and EDC tip capacity ...........76 U7-18 Relationship between the predicted CAPWAP total capacity and EDC total capacity .....77

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11 U7-19 CAPWAP analysis output for bent 4 pile FA blow #300 ..................................................78 U7-20 CAPWAP output results for bent 4 pile FA blow #300.....................................................79 U8-1 The orientation of box and electrodes for each mixture ....................................................87 U8-2 Location of corrosion probes relative to the bottom of pile cap in the 24-in piles ............87 U8-3 The mapping between electrodes and wires in the electrical box by color of wire and inlets ...................................................................................................................................88 U8-4 The surface electrode contact location when measuring the external corrosion potential of each individual electrode ................................................................................88 U8-5 Locations of electrical boxes on the bridge pile ................................................................89 U8-6 Surface resistivity and external potentials measuring locations ........................................89 U8-7 Initial electrical potent ial reading taken on 5/8/2007 ........................................................90 U8-8 Initial electrical potent ial reading taken on 6/26/2007 ......................................................90 U8-9 Second electrical potenti al readings taken on 06/29/08 .....................................................91 U8-10 Location and mapping of wires and electrodes in the durability segment .........................92 U8-11 Potential readings external electrode contact locations ...................................................93 U8-12 Wenner linear four-probe array and display ......................................................................93 U8-13 Initial surface resistiv ity reading taken on 5/8/2007 ..........................................................94 U8-14 Initial surface resistiv ity reading taken on 6/26/2007 ........................................................94 U8-15 Second surface resistivity reading taken on 6/29/2008 ......................................................95

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12 Abstract of Thesis Presen ted to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Master of Science IMPLEMENTATION OF HIGHLY REACTIVE POZZOLANS IN THE KEY ROYALE BRIDGE REPLACEMENT By Yen Chih Tsai December 2008 Chair: H. R. Hamilton Major: Civil Engineering The Florida Department of Transportation (F DOT) recently completed construction on a small concrete bridge construc ted with precast, pretensioned piles located in a coastal environment. Six different concre te mixtures were used to cons truct the piling. They contained fly ash, ultra-fine fly ash, ground granulated blas t furnace slag, metakaolin, and silica fume. The sixth mixture was a Portland cement-only control with no supplementary cementitious materials used. Funding was provided for this work from the Federal Highway Ad ministration Innovative Bridge Research and Construction Program, which helps state, county and local bridge owners incorporate innovative materials a nd technologies in their bridge projects. The focus of the project is to investigate the longterm durability of the piles cons tructed with these new materials when in a marine environment. This thesis covers the design, construction and early monitoring of the piles. The second objective of this project is to evaluate the new pile driving monitoring system, Embedded Data Collector (EDC). Redu ced strain and acceleration, pile stresses, and pile capacities collected using EDC were comp ared to the data collected from using the conventional monitoring system, Pile Driving Analyzer (PDA).

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13 CHAPTER 1 INTRODUCTION The Florida Departm ent of Transportation has se t a goal to build bridges that will last at least 100 years. Currently, accepta nce criteria consist of measuri ng the plastic properties, waterto-cementitious ratio and compressive strength. None of these acceptance criteria can be used to predict the ultimate service life of the structure. By performing more durability-related tests on local materials, the Department can develop a better understanding of how long a structure can be expected to last. To ensure the longest possi ble service life from bridge s constructed in a marine environment, current FDOT design standards (F DOT 2008 Structures Manual) require the use of silica fume in the splash zone of piles in a marine environment. The splash zone is the vertical distance from 4 feet below mean low water (MLW) to 12 feet above mean high water (MHW). Under new specifications proposed by AASHTO other supplementary cementitious materials (SCM) designed to reduce the permea bility of concrete could be allowed. These newer materials require investigation to determine which design criteria should be implemented in order to provide the desired service lif e to Department structures. Innovative Bridge Research and Construction (IBRC) funding was secured by the Florida Department of Transportation (F DOT) to aid in constructing a nd instrumenting a bridge in coastal waters that contained se veral of the new highly reactive SCMs that are now available for use to reduce concrete permeability and that are being considered for the AASHTO Construction Specification. This report outlin es the bridge design, instrumentation, construction, and early data gathered from the Key Royale Drive Bridge in Sarasota, FL

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14 CHAPTER 2 STRUCTURE DESCRIPTION The prim ary objective of the project was to inve stigate the long-term durability of the piles in a marine environment under real time conditions Key Royale Drive Bridge, located on Anna Maria Island, in Manatee County, Florida was se lected for the implementation of the highly reactive SCM. The bridge is located in a primar ily residential area with light vehicle traffic traveling at slow speeds. The superstructure is a five-span co ntinuous slab girder supported by pile bent substructures ( Figure 2-1)and is located in a canal that is connected to the Gulf of Mexico. The substructure components are two (2) end bents and four (4) intermediate bents, with five (5) driven precast, pretensioned conc rete piles in each bent Two pile sizes are highlighted in the foundation schematic shown in Figure 2-2 The 24-in. square piles are the bridge foundation piles while the 18 -in. square piles are sacrificial piles that will be pulled and autopsied som e time in the future to determine how well each concrete is performing. Although unnecessary because the canal is not navigable, the piles were placed in a fender configuration for aesthetic reasons. The contract for the bridge construction was let in April of 2006. The bridge that was to be replaced had to be demolished in phases because it was the only bridge that connected a portion of the island with the mainland. Consequentl y, the construction was divided into 2 phases. During the first phase, two lines of piles were in stalled for continued tra ffic flow while phase II was being completed. A series of highly reactive SCMs were employed in the concrete used to produce the piles including fly ash (FA), ultra-fi ne fly ash (UFA), ground granulat ed blast furnace slag (BFS), metakaolin (MET), and silica fume (SF). As indicated in Figure 2-2 each bent contains five piles, each p roduced with different mixture designs The designations and mi xture details will be

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15 discussed more fully later in this report. This created a series of high pe rformance concretes that are exposed to the same severe environment pr oviding a relative comp arison of performance over a long period in actual service conditions. Th e sacrificial fender piles were produced with the same concrete and the same time as the respective bridge piles. One additional sacrificial pile was produced with no SCMs (CEM). Co mpanion durability segments were also constructed with same concrete used in the brid ge and fender piles. These were hung from the fender piles in the splash zone and were more heavily instrumented than the bridge or fender piles. Extensive material testing was conducted duri ng and after constructi on of the piles to document the mechanical characteristics of each of the plant produced mixtures. These data are documented in this report for use in eval uating performance of the bridge piles. Instrumentation in the bridge piles includes a ccelerometer/load cells at each end of the pile to allow determination of the impact forces generated during driving. These readings are documented in this report along with a comparison with traditional PDA re sults also taken from the same piles. Initial readings were taken from the corrosi on instrumentation soon af ter completion of the bridge and are documented in this report. These readings are expected to provide the data against which future readings can be compared.

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16 Figure 2-1. Key Royale Drive Bridge was selected for this project Figure 2-2. Bridge founda tion plan showing bridge and fender pile layout PHASE 2 UFA FA SF BFS MET CEM UFA FA SF BFS MET 24-in square bridge pile 18-in square fender pile PHASE 1 BENT 1 BENT 3BENT 4BENT 5BENT 6 BENT 2 NORTH

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17 CHAPTER 3 CONCRETE MIXTURE DESIGNS Thirteen m ixture designs containing a variet y of highly reactive SCMs were prepared in the FDOT State Materials Office Laboratory. The details of this testing are covered in Roske (2007). The goal was to optimize the mixture proportions to maximi ze the strength and durability characteristics of conc rete. Fly ash (FA), ultra-fine fly ash (UFA), ground granulated blast furnace slag (BFS), metakaolin (MET), and silica fume (SF) were all considered. The laboratory work involved preparing spec imens from mixtures with the proportions listed in the table. The following tests were conducted for each mixture series: ASTM C 78 Flexure Strength of Concrete ASTM C 157 Length Change of Hardened Hydraulic-Cement Mort ar and Concrete ASTM C 642 Voids in Hardened Concrete ASTM C 1012 Length Change of Hydraulic-Cement Mortars E xposed to a Sulfate Solution ASTM C 1585 Measurement of Rate of Absorption of Water by Hydraulic-Cement Concretes FM5-578 Resistivity as an Electrical Indicator of its Permeability NT Build 492 Rapid Chloride Migration Water Permeability Modulus of Elasticity Selection of the final mixture proportions fo r the bridge piles was based on a decision matrix, which weighted durabilit y, physical properties, and cost The laboratory tests were divided into two major categories: physical and durability results. The test results were normalized to the results of the tests on the contro l mixture. The data were normalized such that ratings that were less than 1.0 were considered an improveme nt over the cont rol results.

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18 A single rating for each mixture was then comp iled. The relative importance of durability and physical results were weighted at 50% and 40%, respectively. The remaining 10% was assigned to cost. The average price per ton of ea ch material was identified and then amassed to determine a normalized cost value. After the precast supplier had been selected th e selected mixture designs were adjusted to accommodate their particular plant practice and typical materials. Final mixture designs used to produce the concrete for the piles are shown in Table 3-2 and Table 3-3 with the mixture identifier shown in Table 3-1

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19 Table 3-1. Notation used to denote 6 mixtures used in bridge piles Designation SCM CEM None SF Silica Fume+Fly Ash MET Metakaolin+Fly Ash UFA Ultra-fine fly ash+Fly Ash BFS Blast furnace slag+Fly Ash FA Fly ash Table 3-2. Mixture designs selected for use in CEM, UFA, and FA piles PHASE I Material Producer Type CEM UFA FA Coarse Aggregate GA-553 #67 1840.0 1840.0 1840.0 Fine Aggregate 36-491 Silica 806.0 806.0 806.0 Cement Suwannee American Type II 970.0 670.0 795.0 Fly Ash ISG Type F 0.0 175.0 175.0 GGBFS Civil & Marine Grade 100 0.0 0.0 0.0 Ultra Fine Fly Ash Boral (Micron3) Type F 0.0 125.0 0.0 Metakaolin Optipozz Type N 0.0 0.0 0.0 Silica Fume Force 10000D (Grace) Densified 0.0 0.0 0.0 Water Local 333.0 333.0 333.0 Air Entr. Admixture Daravair 1000 (Grace) AEA 5.0 5.0 5.0 1st Admixture WRDA 60 (Grace) Type D 28.6 28.6 28.6 2nd Admixture ADVA CAST 540 (Grace) Type F 42.9 42.9 42.9 Table 3-3. Mixture designs selected for use in SF, MET, and BFS piles PHASE II Material Producer Type SF MET BFS Coarse Aggregate GA-553 #67 1840.0 1840.0 1840.0 Fine Aggregate 36-491 Silica 806.0 806.0 806.0 Cement Suwannee American Type II 715.0 695.0 670.0 Fly Ash ISG Type F 175.0 175.0 175.0 GGBFS Civil & Marine Grade 100 0.0 0.0 300.0 Ultra Fine Fly Ash Boral (Micron3) Type F 0.0 0.0 0.0 Metakaolin Optipozz Type N 0.0 100.0 0.0 Silica Fume Force 10000D (Grace) Densified 80.0 0.0 0.0 Water Local 333.0 333.0 333.0 Air Entr. Admixture Daravair 1000 (Grace) AEA 5.0 5.0 5.0 1st Admixture WRDA 60 (Grace) Type D 28.6 28.6 28.6 2nd Admixture ADVA CAST 540 (Grace) Type F 42.9 42.9 42.9

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20 CHAPTER 4 PILE DESIGN AND CONSTRUCTION Design The bridge was designed by Avart Consulting Engineers under the supervision of FDOT District One. Based on the two soil borings taken for this project, the soil divides approxim ately into three layers. The soil boring was taken from elevation + 10 to elevation -80. The top 40 feet of soil is poorly graded sands and gravelly sands. The following 30 feet is combination of inorganic clays of high plasticity and fine sands or silt. The last 20 feet is all sa nd-silt mixtures. Pile design was based on standard FDOT drawings from the State Structures Design Office. The selected strand pattern for the 24-in. bridge p ile was 20 -in. diameter special low relaxation GR270 seven-wire strands evenly distributed around the perimeter ( Figure 4-2 ). The selected strand pattern for the 18-in. fender pile was 12 in. diam eter strands we re evenly distributed around the perimeter (Figure 4-2 ). According to the structural plans each strand was to be prestressed to 34.0 kips. This results in a calculated prestress level of 1,180 psi for the bridge piles and 1,260 psi for the fender piles. The de sign calls for a m inimum prestress of 1,000 psi after losses with no loads applied. Both piles we re designed with 3-in. of clear cover over the spiral ties as required by FDOT for piles in marine environments. The design concrete strength fc was 6,000 psi at 28-days. The design also called for a minimum compressive strength of 4,000 psi at the tim e of prestress transfer. Fender piles were also fabricated that were 18 in.-square x 45-ft long. The required pile lengths were such that splices were not needed. The control CEM mixt ure design was only used to cast two 18 in. x 18 in. x 45 ft fender piles. For each 24-i n. bridge pile and 18-in. fender pile ( Figure 4-2 ), 20 -in. and 12 -in. diam eter strands were evenly dist ributed around the perimeter. Each strand was prestressed to approximately 34.0 kips according to the structural plans.

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21 Pile Production and Material Sampling Six bridge p iles, two fender piles and one durability segment were produced from each mixture. Four of the bridge p iles (for the intermediate bents) were 85-ft. long and two of the bridge piles (for the end bents) were 70-ft. long. The fender piles were 45-ft. long. The six piles and single durability segment were cast in a single bed during a single production run of concrete. This ensured that all of the piles contained the same concrete, prestressing strand and were prestressed to the same level at transfer. Two additional fender piles using the mixture without SCMs were cast separately. Prestressing strand was pulled using standa rd plant practice and according to FDOT specifications. Elongation and force were monito red and recording accord ingly. The stressing dates for each pile are shown in Table 4-1 Before casting the piles, corrosion instrumentation was insta lled. Piles were cast using concrete buggies with 5 cy capacity ( Figure 4-4). The on-site batch plant m ixed a sufficient quantity of concrete for the buggy and discharged for transport. Typical time from mixture discharge to placement in th e forms was approximately 10 minutes. Lifting loops made of bent strand sections were stabbe d into the concrete imme diately after screeding ( Figure 4-5). Curing, Prestress Transfer, and Transportation Imm ediately after the piles were cast, burla p was applied to the exposed surface and a sprinkler maintained moist curing conditions for th ree days as required by FDOT for piles in a marine environment ( Figure 4-6 ). After curing and when the concrete reached sufficient com pressive strength, the strands we re torch-cut to transfer the pres tress. The piles and segments were then lifted out of casting bed and placed adjacent to the pr estressing bed. The lifting loops were then torch cut and Pilgrim EM 5-2 epoxy was applied to the area to provide corrosion

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22 protection ( Figure 4-7 ). During installation of th e lifting loops, a small foam piece was pushed into the concrete around the lifting loops. This allowed the loops to be cut below the surface of the concrete. The epoxy was then applied to prov ide protection. These epoxy area of pile were all cut off after the piles were dr iven to the final elevation. Previ ous research has shown this area to be particularly prone to corrosion. After removal of the lifting loops the piles were then stored at the prestress yard awaiting transportation. The durability segments and sa mple segments were transported to UF to complete instrumentation and allow sampling. Sampling Extensive m aterial sampling was conducted to ensure that the mechanical properties were well documented. Molded samples were obtained from the buggies during the pour as shown in Figure 4-8 Additional samples were cored from a shor t segment of concrete that was cast when the piles wer e cast ( Figure 4-9 ). This allowed comparison of the molded specimens to the cored specim ens. Each sample segment was cast at sa me time with each set of fender piles along with the durability segments. Therefore, the segments were made of the same concrete mixture as fender piles. Sample segments were cast in 18in pile casting bed, but only 10.5 of the casting bed width was used for sample segments. Rema ining 7.5 of the casting bed width was used for durability segments. Table 4-2 and Table 4-3 show an outline of the number and types of sam ples taken from each mixture for laboratory testing. Also, Table 4-5 through Table 4-10 show a summary of the mate rials testing results. The testing was conducted in accordan ce with the following standards: ASTM C 39 Compressive Strength of Cylindrical Concrete Specimens ASTM C 496 Splitting Tensile Strength of Cylindrical Concrete Specimens

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23 ASTM C 78 Flexural Strength of Concrete ASTM C 469 Static Modulus of Elasticity and Poissons Ratio of Concrete in Compression FM 5-578 Concrete Resistivity as an Electrical Indicator of its Permeability NTBuild 492 Chloride Migration Coeffi cient from Non-Steady-State Migration Experiments ASTM C 512 Creep of Concrete in Compression ASTM C 642 Density, Absorption, a nd Voids in Hardened Concrete Deformation of concrete resulting from creep and shrinkage is importa nt in the design of prestressed concrete structures. The concrete stresses due to pres tressing force are sustained in nature, and the resulting concrete creep is an important cause of loss of prestress force and significant changes in deflection. Table 4-9 shows the creep coefficients for all the mixtures. SF has the lowest creep coef ficient among all the mi xtures. Buil and Acker (1985) has found the SF has no effect on basic creep but significantly reduces the drying creep. Creep coefficient of FA was observed to be closed to CEM. Lohtia et al. (1976) has found out the creep behavior of FA concrete is similar to CEM. However, UF A has higher creep coefficient than CEM. High early compressive strength is desirable to allow prestress transfer as early as possible so that the precast plant can minimize the time n eeded in the prestressing bed. Furthermore, high early compressive strength is needed to prevent pile damage during driving. Figure 4-10 shows the com pressive strength gain curves for all th e mixtures. All mixtures except MET have higher strength than the CEM at 28 days. SF has the highe st strength at this point because of its high reactivity at early ages. At 365 da ys, all the mixtures have comp ressive strengths well above the CEM mixture. Due to miscalculating the quant ity of UFA samples, there were not enough UFA samples for 365 days testing.

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24 Adequate tensile strength of concrete is impor tant during prestressing and pile driving to prevent cracking. Beam tests we re conducted to determine the m odulus of rupture (MOR). ACI 363R-92 (1997) has recommended using the followi ng formula as a prediction of the tensile strength of concrete as measured by the MOR from the compressive strength: cf MOR '7.11 (4-1) where fc is the compressive strength (psi). Table 4-11 shows the MOR and compressive strength results for all of the m ixtures, along with the calculated coefficients based on the tested 28-day compressive strength. At 28 days, MOR fo r MET, FA, UFA, and CEM were all less than that suggested by ACI. The 28 day MOR for BFS and SF, however, are well above the CEM mixture, indicating that these mineral admixtures appear to be reacting more quickly than the others. The primary objective of this project was to ev aluate the long term dur ability of concrete piles made with highly reactive admixtures. Protection of the reinforcement depends on improving the resistance of concrete to the ingre ss of the chlorides. Surface resistivity has been shown to be an effective tool to estimate the permeability of concrete. Consequently, samples were taken and tested for surface resistivity. It is anticipated that these data will be compared to chloride penetration data taken fr om the actual bridge after seve ral years of exposure, which will provide a calibration of the surface re sistivity laboratory results. Figure 4-11 shows the surface resis tivity curves for all the mi xtures. At 28 and 91 days, all mixtures have higher SR values than the CEM mixture. SF and BFS have the highes t SR values at this po int, yet again indicating the high early reactivity of these admixtures when compared to the others. Note that 365-day results are not available for the UFA samples. It is anticipated, however, based on the early results, that UFA will have SR values comp arable to SF and BFS mixtures at 365 days.

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25 According to FDOT specifications, concrete th at contains SF, MET, and UFA should have SR value equal or higher than 29 at 28 days. Only SF has SR value higher than 29 at 28 days. Currently, there is not any speci fication for FA and BFS. The rapid migration test NT BUILD 492 (1999), another electrical conductivity test, was also conducted on specimens gathered during pile casting. Figure 4-12 shows the average NonSteady-State Migration coefficient cu rves for all mixtures. The coefficient gives an indication of the permeability of the concrete. A smaller co efficient indicates a less permeable concrete. Consequently, some of the 56 day test results are puzzling. It is expected that the FA mixture would have a higher coefficient than that of the CEM only. Furthermore, the UFA mixture is markedly less than the other samples at 91-days, but changes little at 365-days. Perhaps there were problems with specimen preparation or testi ng at this age. The other mixtures, however, had lower RMT coefficients than the CEM mixt ure at 365 days including FA. In addition, the highly reactive SCMs all had comparable coefficients at this age, which indicates that durability performance should be markedly be tter than the CEM and FA mixtures

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26 Table 4-1. Pile casting schedule Piles Strands Pulled Pile Cast CEM18 6/15/06 6/16/06 UFA24 6/5/06 6/6/06 UFA18 6/8/06 6/9/06 FA24 6/22/06 6/23/06 FA18 6/15/06 6/16/06 SF24 9/28/06 9/29/06 SF18 9/28/06 9/29/06 MET24 10/12/06 10/13/06 MET18 10/12/06 10/13/06 BFS24 10/5/06 10/6/06 BFS18 10/5/06 10/6/06 Table 4-2. Summary of number and types of samples taken fr om each mixture (F 18fender pile) Mixture Type of samples 4-in.dia x 8-in. cylinder 6-in.dia x 12-in. cylinder 4-in. x 4-in. x 14-in. square beam Cored 4-in.dia x 2-in. cylinder from 5 ft sample segment CEM 18 9 5 8 UFAF 18 9 5 8 FAF 18 9 5 8 SFF 18 9 5 8 BFSF 18 9 5 8 METF 18 9 5 8 Table 4-3. Summary of number and types of samples taken from each mixture (24bridge pile) Mixture Type of samples 4-in.dia x 8-in. cylinder UFA 9 FA 9 SF 9 BFS 9 MET 9

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27 Table 4-4. Summary of types of sample used in each test Concrete Property Type of sample Compressive strength 4in.dia x 8-in. cylinder Split tensile strength 4-in.dia x 8-in. cylinder Modulus of rupture 4-in. x 4-in. x 14-in. square beam Modulus of elasticity 4-in.dia x 8-in. cylinder Surface resistivity 4-in.dia x 8-in. cylinder RMT Cored 4-in.dia x 2-in. cylinder from 5 ft sample segment Creep Coefficient 6-i n.dia x 12-in. cylinder Voids and Absorption Cored 4-in.dia x 2-in. cylinder from 5 ft sample segment Table 4-5. Summary of mechanical properties (a) (F 18fender pile) Mixture Compressive strength (psi) Split tensile strength (psi) 28 days 91days 364 days 28 days CEM 6,730 7,500 8,740 870 UFAF 6,500 8,300 N/A 840 FAF 6,160 7,990 8,380 780 SFF 6,200 8,850 9,300 510 BFSF 8,870 10,050 10,610 820 METF 6,520 7,580 9,290 740 Table 4-6. Summary of mechanical properties (b) (F 18fender pile) Mixture Modulus of rupture (psi) M odulus of elasticity (ksi) 28 days 28 days 91 days 364 days CEM 890 N/A 4,690 5,700 UFAF 890 N/A 4,200 N/A FAF 860 N/A 4,300 5,180 SFF 1,220 N/A 5,080 5,240 BFSF 1,260 3,860 5,500 5,200 METF 930 3,310 4,580 4,770 Table 4-7. Summary of mechani cal properties (24bridge pile) Mixture Compressive strength (psi) 7 days 28days 364 days UFA 4,940 7,550 N/A FA 5,890 7,780 9,080 SF 6,700 8,040 9,840 BFS 5,080 7,560 10,610 MET 5,730 6,540 9,170

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28 Table 4-8. Summary of durability properties (a) (F 18fender pile) Mixture Surface resistivity (k -cm) RMT, Dnss m (x 10-12 m2/s) 28 days 91 days 364 days 56 days 91 days 180 days CEM 13 15 17 76.2 45.9 66.7 UFAF 16 83 N/A CP 3.9 2.5 FAF 12 38 75 11.8 17.1 12.5 SFF 96 130 225 137.5 46.1 7.2 BFSF 52 92 259 118.4 N/A 2.6 METF 24 27 84 49.6 96.0 15.7 *Note: CP Complete Penetration Table 4-9. Summary of durability properties (b) (F 18fender pile) Mixture Creep Coefficient CEM 1.21 UFAF 1.83 FAF 1.23 SFF 0.22 BFSF 0.96 METF N/A Table 4-10. Summary of durability properties (24bridge pile) Mixture Surface resistivity (k -cm) 7 days 28 days 364 days UFA 5 17 N/A FA 7 46 63 SF 19 83 222 BFS 49 72 259 MET 12 24 84 Table 4-11. Modulus of rupt ure, compressive strength, a nd coefficient at 28 days Mixture 28 days fr (psi) fc (psi) fr / fc UFA 889 7550 10.2 CEM 893 6730 10.9 FA 857 7780 9.7 SF 1218 8040 13.6 BFS 1262 7560 14.5 MET 933 6540 11.5

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29 Figure 4-1. Spiral ties spaci ng for 18-in & 24-in piles A B Figure 4-2. Cross section of squa re piles. A) 24-in. B) 18-in Figure 4-3. 18-in fender pile with prsstressed strands been pulled A A 5 Turns @ 1" Pitch 16 Turns @ 3" Pitch 6" Pitch 16 Turns @ 3" Pitch 5 Turns @ 1" Pitch Sprial Tie 1" Spacing 1" 3" 3" 3/4" by 3" Chamfer (Typ.)Elevation 24" 24" 3" Cover (Typ.) 18" 18" 3" Cover (Typ.)

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30 Figure 4-4. Pile cas ting at precast yard Figure 4-5. Lifting loop we re stabbed into the co ncrete after screeding

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31 Figure 4-6. Moist curi ng at precast yard Figure 4-7. An epoxy was applied to the area for corrosion protection

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32 Figure 4-8. Molded cylinders and beams were used to sample the concrete from each representative mixture A B Figure 4-9. Sample segment with debonded strands from which cores were taken. A) Side view. B) Top view

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33 Figure 4-10. Compressive strength of all mixtures at 28, 91, and 365 days Figure 4-11. Surface resistivity of all mixtures at 28, 91, and 365 days 0 2000 4000 6000 8000 10000 12000 0100200300400Age (Days)Compressive Strength (psi) FA SF BFS MET CEM UFA28 Days 365 Days 91 Da y s 0 50 100 150 200 250 300 0100200300400 Age (Days) Surface Resistivity (k-ohms-cm) FA SF BFS MET CEM UFA28 Days 365 Days 91 Days

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34 Figure 4-12. RMT of all mixtures at 56 and 365 days 0.0 20.0 40.0 60.0 80.0 100.0 120.0 140.0 160.0 050100150200 Age (Days) Dnssm (x 10-12 m2/s) CEM FA SF BFS MET UFA56 Days 365 Days

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35 CHAPTER 5 PILE INSTRUMENTATION Overview Accelerated corrosion testing in labo ratory conditions is commonly used to evaluate the relative performance of material s and systems under typically unrealistic harsh conditions. The construction of the Key Royale Bridge allows an opportunity to monitor subs tructure elements in a marine environment under realistic exposure conditi ons at real time. To ensure that as much data as possible is obtained from the bridge instrumentation was designed to be monitored periodically over several years rath er than continuously. Another ke y element in the plan is that sacrificial elements such as the durability segments and fende r piles were included in the construction. These elements can be destructiv ely sampled or even removed without affecting the bridge serviceability. Elect ronic measurement systems that take measurements continuously were avoided due to the maintenance needed a nd unknowns concerning the se rvice life of such systems. Corrosion Sensors Electrodes were cast into the c oncrete with wiring arranged in an electrical box at the surface to allow period ic measurements using portab le electronic devices. Bridge piles in bent 3 and 4 were instrumented with these corrosion sensors as shown in Figure 5-1 The corrosion sensors consisted of titani um and steel electrodes ( Figure 5-2). The steel electrode was fabricated from a short piece of grade 60 reinfo rcing bar and will be used to measure corrosion potential and as the working electrode when meas uring corrosion rates. The titanium electrode will be the counter electrode fo r use in measuring corrosion rates of the steel bars. The electrodes were oriented in the same plane as the prestressing st rand so that the clear cover was

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36 the same as that of the strand ( Figure 5-3 ). In addition, the electrodes were fixed in place with nonconductive m aterial to ensure no electr ical contact with the strands. Terminals in the electrical junc tion box formed by soldering the copper stranded lead wires to stainless steel bolts. The solder ed connection was then coated w ith the scotch-kote. Each bolt was covered with a rubber cap to prevent any contacts between the wires that may cause any closed circuit. It is recommended that after each periodical reading, a new layer of scotch be placed on the connection in order to prevent the corrosion of wires and extend its life. Each pile was instrumented with two sets of corrosion sensors. One set was installed approximately 2 ft above the mean high water level (MHW). The second set was installed 2 ft above the splash zone for data comparison purpose. Leads from the corrosion sensors were terminated at an electrical box to allow quick connection for measurement. Corrosion sensors were fabricated at UF and installed at the prestress yard by UF personnel. These corrosion sensors underwent quality control (stability of natural potential readings on titanium electrodes) at FDOT State Materials o ffice (SMO) by UF staff. Embedded Data Collector Bridge piles in bents 3 and 4 were instrum ented with embedded data collectors (EDC). Each EDC is composed of a strain gage and accelerometer along with a battery and on board data collection and transmission capability ( Figure 5-4). Four EDC units were installed along the pile leng th in the locations shown in Figure 5-1 and were used to monitor the pile during driving. Data collected f rom strain gauges a nd accelerometers is used to compute the stress levels and static pile capacity of the pile in the real time and saved in the binary file for future use. Such readings provide quali ty control during the driving so that piles are not overdriven or damaged. EDC also includes a battery and radio transmitter for wireless data transmission to a

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37 receiver attached to a lap top computer. EDC units were installed and monitored during driving by Applied Foundation Testing (AFT). Loca tions of EDC were determined by AFT. If desired in the future, EDC can also be us ed for the long term m onitoring. Wave speed, reflection depth and shapes of the waves under a lo ading condition (the truck load is consistently used for tests) can provide insi ght into material changes over th e years. Especially wireless aspect of the data acquisition seems to be advantageous for the long term, multiple data collection and gives opportunity to connect the EDC network to the existing data acquisition systems implemented by FDOT in the past years. Covermeter The purpose of this research is to verify the accurate dep th of the prestressing strands within the 24-in piles for the IBRC project. The reason for the depth verification is due to the fact that corrosion sensors will be utilized for th e pile strands and, thus an accurate measurement of concrete cover is needed to make assumptions about the ingress and migration of deleterious substances to the strands. A total of five measuring locations will be re quired for each pile. The depth of cover at the pile tips will be required and performed with a ruler. The e nd measurements also serve a good location for the calibration of the covermeter prio r to testing. The coverm eter will be used in three locations to confirm depth of cover of the embedde d steel within the pile. For the 70 ft piles the covermeter will measur e depth of cover 15 ft from each end and at the midpoint of the pile; 35 ft from the end. For th e 85 ft piles: the covermeter will be used to measure depth of cover 20 ft from each end and at the midpoint of the pile 42.5 ft from the end. Each 24-in pile has a total of 20 strands which require a tota l of 24 depth measurements. The depth measurements will be performed as per configuration provided by Figure 5-6.

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38 Figure 5-1. Location of corrosion sensors and EDC A B Figure 5-2. A) #3 steel el ectrode with 2-in length of the electrode exposed. B) 3-in titanium electrode with 2-in length of the electrode exposed 85' 17' 24' 20' 20' 4' EDC NGDV "0" elev. mean water level MHW +1.12' MLW 0.32' Cut-off elevation 2' Electrical Box Corrosion Sensors Top of Pile Cut-off elevation Electrical box Corrosion sensors Mean water level MHW +1.12 ft MLW -0.32 ft 2' 2' 4'

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39 Figure 5-3. Wired corrosion sens ors (top-titanium, bottom-steel) Figure 5-4. Smart sensors and corrosion probes on the right

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40 Figure 5-5. Battery and radio transmitter are included for wireless data transmission Figure 5-6. Cross-Sectional View of 24 pile with strand nomenclature and layout

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41 CHAPTER 6 DURABILITY SEGMENT Overview The differences in final elevation of the bri dge piles resulted in a variation of the final eleva tion of the corrosion sensors relative to th e water line. This difference will affect the corrosion readings due to the variation in the exposure conditions at ea ch of the corrosion sensors. To ensure a uniform exposure at th e corrosion instrumentation, short slab-shaped concrete sections (durability segments) were cast at the same time and using the same concrete and prestressing strand as the fender piles. Th ese segments were instrumented with corrosion sensors and temperatures sens ors for periodic monitoring. The segments were installed after construc tion was completed by clamping and strapping the segments to the fender pile using the galvanized clamp and stainless steel straps ( Figure 6-1). This enabled precise location of corrosion se nsors in the splash zone, where corrosion developm ent is critical for the structure. One segment per mixture was cast. These segments will also eventually be core d for evaluating the chloride ion pe netration and concrete hydration over time. Design and Construction Durability s egments were cast with each set of fender piles. Therefore, they are made of the same concrete as fender piles. In some cases fender piles were also cast simultaneously with the main 24-in piles. Since durability segments were produced in 18-in pile casting beds but 18-in thickness of segments was not favorable during attaching segments to the fe nder piles, only 7.5-in of the casting bed width was allotted for the durability segment ( Figure 6-3 ). As described in the

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42 material sampling of this report, the remaini ng portion of the segment was used to produce sample segment for coring cylindrical samples for the material tests. Pile casting bed was divided usi ng a 5/8-in thick plywood sheet (Figure 6-3). Since sample segm ents were to be cored for laboratory testing, some strands were debonded to allow removal before coring. Concrete was poured and vibrated in the sample segm ent first, thus fresh concrete pushed the plywood against the debonded strands. Th en, the concrete was placed and vibrated in the durability segment of the casting bed. Precautions were provided not to damage the installed corrosion probes and thermocouples. After curing and when the concrete reached sufficient compressive strength, the strands were torch cut to transfer the prestress. The samp le segments were then lifted out of casting bed and placed adjacent to the prestressing bed. Then, the segments were transported back to UF for testing. Eight cores were taken from the each sample segment. From these cores, the appropriate specimen could be cut. Since the durability segments were designed for future corrosion monitoring and evaluation, the segments were repaired in the way that the prestressing stra nds in the segment are not exposed to any salt water attack on both sides of the segment. The concrete and strands were chipped and cut below the concrete surface. Then, Styrofoam was used to construct the formwork around the durability segment ( Figure 6-6 ). Last, Sikadur 32 hi gh m odulus structural epoxy was mixed with sand and applied to the dur ability segment. Approxi mately 1-in thickness of the epoxy was poured into the formwork. Figure 6-6 shows the final repaired durability segm ent. Corrosion Instrumentation Three sets of corrosion sensors were insta lled in each segment ( Figure 6-7 ). Segments were attached to the fend er piles such that cent ral set of probes is in the splash zone. Bottom set

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43 is on the MHW level and top set of sensors is ab ove the splash zone. Corrosion is expected to occur in the splash zone, ther efore top and bottom se t of sensors are for comparison purpose. Temperature Instrumentation Therm ocouples were installed only in the dur ability segments. They are used to measure temperature gradient in the cover zone, which depends on the concrete properties. Therefore temperature instrumentation is in tended to monitor for concrete changes over the life of the structure. Three thermocouples were placed in the central portion of the segment ( Figure 6-7 ), which is in th e splash zone, where corrosion is the most intensive. They are spac ed 1-in from the other toward the surface of the segment, such that 1s t thermocouple is aligned with strands, 2nd lies 1in toward the surface and 3rd is located 2-in toward the segment surface (designed concrete cover was 3 inches). Thermocouples were attached to the strands using a cantilever grip shown in Figure 6-8 System atic measurements (ever year) of the te mperature gradient in the cover zone provide a baseline value. Once concrete deteriorates (micro -cracks, voids, moisture content, etc.); trend in the readings should change accordingly. This will indicate corrosion potential on the strands and should be compared with other corrosion readings and NDT data testing.

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44 Figure 6-1. Durability segment af ter installation on the fender pile Figure 6-2. Durability segments we re attached to the fender piles FenderFront View Existing ClampSide View Pile 1/8" Neoprean Pads Zero Elevation New Clamp & Nut 3/4" SS Strapes 1/2" Dia. 316 SS Ancho r e ach side for lifting Durability Segment Electrical Box Fender Wood Block

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45 Figure 6-3. Durability segment and sample segment construction Figure 6-4. Sample segment and durability segment were divided by a plywood sheet Bonded Strands (typical) Debonded Strands (typical) 5/8" plywood C C Section C-C Sample Segment D urability Segment Corrosion Sensors 5 ft 7.5-in10.5-in

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46 Figure 6-5. Sample segment and durability segments after concrete been poured A B Figure 6-6. Repair of durability segment. A) Before repair. B) After repair

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47 Figure 6-7. Instrumentation in the durability segment Figure 6-8. Thermocouples grip system

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48 CHAPTER 7 PILE DRIVING Method of Installation For piles in bent 3 and 4, 42-in diameter stee l casing was installed first using the vibratory hammer before leading holes were predrilled to elevation -60 using 32-in diam eter auger drill. Piles were then lowered into the predrilled holes and casing. Because some of soils were spilled out of drill into the casing duri ng the lifting of drill, there were some left over soils at bottom of the casing. Finally piles were driv en to approximately 1 foot be low the casing into the soil until refusal of the hammer was reached. The final tip elev ations of these piles in bent 3 and 4 were at around -61. This method of installation was used becau se the location of bridge is in a primarily residential area. Predrilled hole and casing can minimize the extremely loud noise created during pile driving. UF persons were there to ensure that each representative pile was driven to the correct location corresponding to pile placement key. Driving was monitored by Williams Earth Science using PDA and Applied Foundation Testing using EDC. For the remaining piles, casing and predrilled hol es were vibrated and drilled to elevation 30 before the piles were placed in the casing. Unlik e the piles in bent 3 and 4, piles were driven to about 18 feet below the tip of casing. So, the final tip elev ations of these piles were approximately at -48. Top of the piles were cut to desired cutoff eleva tion after the driving. Pile driving logs were prep ared by the contractor, Cone and Graham. The driving logs show first blow of pile driving started at approx imately 7 feet above the tip of casing. The blow count per foot (bpf) in the casi ng is relatively small compared to the bpf as the pile tip approaches the last 2 feet of the casing. This indicates the hammer wa s not striking the pile perfectly straight down the casi ng or the piles were not ligned straight down through the casing. Consequently, the piles were actua lly striking against the casing as the piles were driven down to

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49 the bottom of casing. When the pile s reached the last foot or 2 feet of casing, the piles were driven into the left over soil that was spilled out during the lifting of the auger drill and eventually through the casing into a stiff soil layer. This can be verified by the large bpf (over 100) for the last 2 feet of dr iving in the driving logs. Monitoring Pile Driving with PDA During the pile driving, Pile Driving Anal yzer (PDA) and Embedded Data Collector (EDC) were used to m onitor driving. Driving monitoring systems were used to monitor the dynamic compressive and tensile stress levels during the driving of the pile to ensure the pile are not damaged by excessive hammering. These system s were also used to estimate the bearing capacity of a pile to ensure the desired pile capacity is reached at end of driving. This section describes monitoring with PDA. PDA is field equipment used to measure stra ins and acceleration at pile top during driving in real time. PDA consist a pair of strain tran sducers and a pair of accelerometers mounted to the outside surfaces of the pile at driving end just before driving begins ( Figure 7-3 ). Strain transducers and accelero meters are connected to cables that send data to PDA computer ( Figure 7-2) for data processing and result s. PDA com putes the total static resistance of the pile using the Case Method. Case Method was developed in 1960s at Case Instit ute of Technology in Cleveland, Ohio. Case Method computes pile ca pacity based on wave mechanics and models hammer, cushion, and pile as a single degree of freedom (SDOF) system. Both PDA and EDC calculate the stress levels in the pile based on one-dimensional wave propagation analysis (Clough and Penzien 1975). The basic axial wave propagation equation is written as following. 2 2 2 2dx u E dt u (7-1)

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50 Where u is the pile displacement at time t and location x, left and right hand partial derivatives are the acceleration and changing strain in the pile, and is the mass density of the pile material. ctxfctxftxu 2 1, (7-2) Equation 7-2 is a general solution of the wave propagation equation shown in Equation 71. The solution implies there are at most tw o possible opposite propagating waves, downward traveling wave with force, Fdown, and the upward traveling wave with force, Fup, traveling through any given point in time ( Figure 7-4 ). Based on kinematics and strength of materials, the force of each traveling wave can be obtained fr o m the particle velocity (V) and the impedance (Z) of the pile. ZVF (7-3) Where pile impedance (Z) can be calculated from the dynamic modulus of the pile material (E), the pile wave speed (c), and cross section area of the pile (A). c EA Z (7-4) Where pile wave speed (c) can be determined from the dynamic modulus of pile material (E) and the density of the pile ( ) E c (7-5) The hammer impact creates a force (P) and part icle velocity (V) at top of the pile. The force is computed by multiplying the measured averag e strain from that pair of strain transducers mounted near the top of the pile by the pile area and modulus of the pile. From statics and

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51 equilibrium, the measured force in the pile has to be equal to sum of the two traveling wave forces. down upFFEAP (7-6) Where is recorded strain from strain the tr ansducers, E is the dynamic modulus of the pile material, and A is cross section area of the pile. Fdown and Fup are the downward and upward traveling force waves in the pi le. The particle velocity (V ) is obtained by integrating the averaged acceleration measured from that pair of accelerometers. The measured particle velocity must be sum of the two tr aveling wave velocities. down upVVadtV (7-7) From above equations, the downward and upward traveling wave forces can be calculated from measured force in the pile (P) a nd particle velocity of the pile (V). 2 )( 2 )( ZVP F ZVP Fup down (7-8) Assuming the pile is linearly elastic and damping only occu rs at pile tip, the equation below was derived to compute the static capacity of the pile (RStatic). This is also called Case method capacity. 2 ) ( )1( 2 )( )1(22 11ZVP J ZVP J Rc c static (7-9) The equation uses the measured force and velocity at T1 and T2. T1 is at peak force and velocity pulse. T2 equals to T1 plus 2L/c. 2L/c is the time required for the downward impact force wave travels from the top of pile to botto m of pile then back to the top of pile. Jc is called case damping value and assumed only occurs at pile tip. Jc is an input to PDA and is recommended based on the soil condition at pile tip. Because only the pile top is instrumented

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52 with the gauges and there is not any information about the pile tip, PDA can not separate the tip and skin resistances from the total pile capacity. Case method calculates the pile capacity base on the download traveling wave at T1 and upward returning wave at T2 assuming damping occurs at the pile tip only. PDA also can used to monitor dynamic compressi ve and tensile stress levels to make sure the pile is not damaged from excessive hammer ing. PDA computes compre ssive stresses at top of pile by dividing the measured forces at pile top by cross sectional area of the pile. Tensile stresses can be can be computed by divi ding the maximum possible sum of upward and downward traveling tensile wave forces in the pile by cross s ectional area of the pile. PDA was also found to be useful in detec ting pile damages from improper handling or excessive driving of the piles from early tension wave return before the reflection wave from the pile toe propagates back to the pile top where all the inst rumentation was mounted. For efficiency purpose, PDA is also capable of monitoring the hammer performance by comparing the amount of energy imparted to the pile by the hammer and energy input to the hammer. The amount of energy imparted to the pile can be ca lculated as measured force multiply measured velocity integrat ed over time. Monitoring Pile Driving with EDC EDC monitoring involves em bedding gages in bo th ends of the pile, which should provide better estimates of pile tip capacity and pile tip stresses. The piles were instrumented with strain gauges and accelerometers in pairs during the casting of the pile at both the top and the base of each pile. This allows the forces generated in the pile during pile driving to be measured not only at top of the pile and also bottom of the pile. EDC also includes a battery and radio transmitter for wireless data transmission to a receiver attached to a lap top computer installed with processing software. EDC can also be used fo r long term monitoring since the sensors and

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53 antenna were instrumented in the pile. EDC can provide insight into the material changes over the years. Unlike PDA, EDC is capable of separating the skin and tip capacities from the total pile capacity and calculating the case damping value. EDC has two sets of gauges embedded at both top and bottom of the pile instead of just mounted to the top of the pile. Since EDC can measure the force and velocity at pile tip directly from the bottom set of gauges, the dynamic skin and tip resistances can be separated. As mentioned before, the measured force in the pile consists of two components, downward and upward traveling force waves ( Figure 7-4 ). (7-10) (7-11) (7-12) (7-13) From equilibrium of forces, the dynamic tip and skin resistances may be readily determined as following. tipup tipdown tip DynamicFF R, (7-14) topuptipup tipdown topdown skin DynamicFF FF R, ,2 2 (7-15) Instead of assuming the case damping coefficien t and damping only occurs at the pile tip (PDA), EDC estimates the case damping coefficient (Jc) by looking at the relation between the 2, top top topdownZVP F 2, top top topupZVP F 2, tip tip tipdownZVP F 2, tip tip tipupZVP F

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54 tip to skin resistance ra tio. McVay et al. (2001) have found that there exists a relationship between the case damping value and the tip to skin ratio. EDC computes the total static capacity using the Case method equation with the calculated damping coefficient. This is also called UF me thod capacity. UF method estimates the static tip resistance from bottom set of gauges using the un loading point method. The static tip resistance equals the measured force when the measured velocity goes to zero which means no damping at that point in time. This value can be obtained eas ily by looking at the forc e and velocity trace of the tip sensors. After the static tip resistance is obtained, the static skin resistance can be easily computed by subtracting the static tip resistance from the UF method capacity. SmartPile Review (version 3.41) is the proces sing software, developed by SSI (Smart Structures Inc.) for EDC monitoring system. After the strain and acceleration data were collected in the field, the data were processe d using SmartPile Review on a desktop computer. SmartPile Review collects, analyzes, and displa ys drive data and calcu lated pile capacity information real-time during pile driving. Smar tPile Review software contains total pile capacities calculated using fixed Jc method, calculated Jc method, UF method, and paikowsky method, stress levels, displacements, estimated damp ing coefficient, and miscellaneous of a blow ( Figure 7-5). Comparison of PDA and EDC Results Six param eters were selected to compare th e results from the PDA and EDC pile driving analyses: Measured force in the pile Measured acceleration Calculated particle velocity Case method capacity of the pile Maximum compressive stress at top of the pile Maximum tensile stress in the pile

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55 Unfortunately, after checking the EDC data fr om all the piles, only five out of ten instrumented piles are valid for comparison with CAPWAP results. Table 7-1 lists the piles and status of instrumentation. Bent 3 pile MET and bent 4 pi le UFA had water ingression issue on the accelerometers. Water moisture or other contaminants may leak into the accelerometer during the concrete curing process and cau se distortion of data on the accelerometer channel. The data acquisition was triggered t oo late for bent 4 pile SF, so the data was acquired too late so the calculations are invalid. The radi o in the EDC for bent 4 pile B FS malfunctioned prior to driving the pile. And, bent 4 pile MET had fully operational tip gauges only. The comparisons of measured force, acceleration, and particle velocity were based on data from a single hammer blow. The comparisons of the capacity and stresses included hammer blow data for the entire driving process. The comparisons presented in the following section are based on bent 3 pile BFS. Comparison of Measured Force, Acceleration, and Particle Velocity Figure 7-6 and Figure 7-7 shows the force and acceleration traces for bent 3 pile BFS at blow #280 recorded at pile top by both EDC a nd PDA. The figures show that there are noticeable d ifferences between the traces record ed by EDC and PDA instrumentation. There are several possible reasons for these differences. Firs t, the differences are likely due to the signal filtering scheme choices of each manufacturer. Signa l filtering is used to eliminate unwanted noise generated by electromagnetic or radio s ources. Noise can also be generated by a conductivity shift within a material. Differences may also be a result of using strain transducers and accelerometers fabricated by different manufact urers, which may have different accuracy. Probably the biggest contribut or was the difference in m ounting technique and location along the pile length. The PDA strain and acceleration were obtained by averaging the measurements taken by pairs of strain transduc ers and accelerometers mounted to opposing faces

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56 of the pile. The EDC strain a nd acceleration were obtained from a single strain transducer and accelerometer that were embedded in the pile. Strain and acceleration measured by the surface mounted gages may not match those of the embedded EDC gages for two reasons. One is that there may be some distortion caused by the att achment of the gages to the surface of the concrete. The second is that strain and wave magnitudes would be different if the pile was subjected to hammer blows th at were not uniaxial. EDC instrumentation at the driving end was in stalled approximately 13 ft lower than that of the PDA to ensure that the embedded gages were not cut off after driving. Different installed location along the pile would also cause differe nt measurements due to energy loss during the propagation or pile damping. Even with th ese possible differences, however, the overall measurements show similar trends and magnitudes. In itial peak value and early traces seem reasonably matched, but later traces appear to diverge due to th e noise or distortion described above. Figure 7-8 shows the calculated particle veloci ty between EDC and PDA, which was obtained by integ rating the measured acceleratio n over time. As expected some magnitude variations do exist, but the overall traces are very similar. The variations not only come from the differences in the acceleration traces, but also the integrati on techniques of EDC and PDA. Integration of acceleration yields the particle velocity and an unknown constant term. EDC and PDA may use different methods to determine the constant. One possible method is to shift the plot so that the trace converges to zero. Another method is to rotate the plot relative to the axes to ensure that the velocity converges to zero. It is not known what method was used for either EDC or PDA results, but the trac es still have similar trends even after the integration.

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57 Comparison of Driving Stress and Pile Capacity Figure 7-9 shows the case method pile capacity pr edicted by EDC (Fixed method) and PDA with constant case damping ratio (Jc) of 0.3. It is expected that the comparison of case method capacity shows similar trends with slight magnitude differences since the case method capacity is calculated from force and particle velocity traces at both peak and at 2L/c. Consequently, the comparison plot shows the predicted case method capacities are almost identical throughout the driving. Figure 7-9 also shows that PDA has more blows than EDC. EDC data was lost late in the driving because the construction method called for the piles to be driven inside the temporary steel casing. The EDC radio and antenna that transmit the data were driven below the top of casing, thus bl ocking the transmission of the signal. Figure 7-10 and Figure 7-11 show the maximum compressive a nd tensile stresses at top of pile predicted by PDA a nd EDC for bent 3 pile BFS. As expected the comparison plots show very similar trends, but EDC predicted slight lower stresses than PDA during the drive. PDA predicts averages of 8.9% and 10.0% higher maxi mum compressive and tensile stresses than EDCs predictions at each blow. Considering the magnitude of the compressive and tensile stresses, these differences are not considered sign ificant. The differences are likely due to the variation in velocity and force traces since the stresses are ca lculated based on the force and particle velocity traces. The overall matches of stresses are acceptable. The ratio of the PDA to EDC driving stress es (PDA/EDC) provides a method to compare the results of the two methods relative to es timating potential pile damage during driving. Table 7-2 shows PDA/EDC of the average m aximum driv ing stresses and pile capacities for all the piles with operational instruments in the Key Roya le Bridge. The labels used in the table are shown in Table 7-3 The PDA predicts averages of 20% and 19% higher m aximum compressive and tensile stresses than EDC s predications at each blow ( Table 7-2 ). It is not known what

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58 causes these significant differences in the stresse s. The differences can cause from all the reasons described in the previous section or other possible instrument problems. Conservatively assuming the constant wave form and magnitude as the wave traveling from top of pile to bottom of pile and vice versa, EDC can estimate the stresses at any given location along the pile by adding the computed Fdown from the top gauges and Fup from the tip gauges at any given location. However, the current SmartPile software is still using the same methods of estimating the stresses as PDA. FDOT is currently in the process of devel oping a database for evaluating the EDC based on EDC instrumentation installed in 120 piles among 38 different bridge projects (Herrera 2008). Table 7-4 shows a summary of the data currently available fro m th e database. It shows that PDA predicts higher maximum compressive and tens ile stresses than EDCs predictions, but by only 10% and 7%. The difference between the averaged PDA/EDC stress ratios from this project and averaged ratios from database is possibly due to the fact that data base results were obtained from many different bridge sites with different driv ing conditions, which woul d cause variations in PDA and EDC predictions. However, the PDA/ EDC maximum compressive stress at pile tip ratio (CSB) from this project ( Table 7-2) falls inside the CSB ratio from database ( Table 7-4). Since EDC can directly m easure the CSB with its bottom set of gauges, the measured CSB from EDC should be more accurate than the calculated CSB from PDA. CAPWAP Analysis of PDA Data CAPWAP a nalyses were also performed on the PDA data to allow comparison of the relative tip and skin resistances with that de termined from the EDC data. FDOT recommends use of CAPWAP to estimate the tip resistance and soil properties for every pile. Once the damping values are obtained, PDA uses these damping values to predict the case method capacity of the pile.

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59 CAPWAP (Case Pile Wave Analysis Program) is a signal matching software program that determines total bearing capacity of a pile, as we ll as resistance distribution along the shaft and at the tip. CAPWAP is based on the wave equation, which models the pile as a series of elastic segments and the soil as a series of elasto-plas tic segments with damping characteristics, where springs represent the static so il resistance and dashpots with da mping represent the dynamic soil resistance. Soil parameters are typically assumed at beginning of the analysis. CAPWAP uses the velocity integrated from PDA acceleration meas urements as a boundary condition to compute the force required to satisfy both equilibrium and kinema tics. This computed force is then compared with the force measured form PDA. If the comput ed force does not match with measured force, the soil parameters are modified and the calc ulation repeated until a good match is reached between the computed force and measured force. Two blows were selected from each pile to perform the CAPWAP analysis. Before running the CAPWAP, the desired bl ow was selected in the PDA processing software and pile properties, such as pile diameter, pile length, or blow count in bpf (blow per foot), were also entered at beginning of the analysis. When se lecting the blow record, there are several key concerns. First, select a blow in which bending is minimized. This can be done by ensuring that the final velocity and force values are zero or the traces oscillate ar ound the zero line. Second, select a blow without unusual spikes or other nois e in the trace. Finall y, final displacement of pile should be relatively close to th e inverse of observed blow count. After the blows were selected and the data were entered, the foll owing signal matching process was used. First, the tip resistance pred icted from EDC was used as a starting point for end bearing. Although this option would not be ge nerally be available for PDA analysis, it was hoped that this would lead to a better match quality. Individual resistance values and total

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60 capacity were then varied to match over the fi rst 2L/c time period until a reasonably good match was achieved. The AC (automatic) routine was then used to improve the overall match. The end bearing, toe quake, and toe dampi ng were modified to improve the match at both 2L/c and right after the 2L/c, where the wave was reflected. To improve the match in the trace after 2L/c, the total capacity, shaft and toe damping values, qua kes, and unloading parameters were modified simultaneously. AQ (Auto Quantity Improvement) routine was also used to quickly find a good combination of the unloading parameters. It was found that the initia l unloading parameters could be adjusted to improve the solution. Cons equently, these parameters were varied followed by use of the AQ routine to find an improved solu tion. These changes may cause the early part of record to change significantly, which th en necessitates repeating the signal matching procedure again. This process was used until a match quality number of approximately 3 or below was obtained. Also the blow count and tota l capacity have to be reasonably closed to the values predicted by PDA. Figure 7-12 though Figure 7-14 show the results of a CAPWAP analysis on Bent 3 pile FA blow #166 of the Key Royale Bridge Project. T h e predicted capacity of the pile, soil properties, unloading parameters, and maximums compre ssive and tensile stresses are given in Figure 7-12 Capacity includes the distribution of shaft resistance, end bearing, and total capacity of the pile. Both com puted and measured blow count and set are also presented CAPWAP models the pile as seri es of elastic segments. In th is case, the pile is divided into 24 segments. Figure 7-13 shows the maximums forces, stre sses, d isplacements, velocity, and transferred energy at each pile segment. Figure 7-14 shows the input pile profile, such as unit weight, elastic m odulus, area, and pile depth, and suggested case damping value to be used in calculating the case method capacity.

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61 This figure also shows other direct case method results, such as the maximum measured pile top force (FMX), the displacement at the end of re cord (DFN), the maximum transferred energy at the pile top (EMX). Figure 7-15 shows the typical pl ots from the CAPWAP analysis of bent 3 pile FA blow #166. The top left plot is the match of measured and computed force. The computed force trace is calculated directly from a velocity input, wh ich is integrated from acceleration recorded by PDA. This match plot gives an agreement betw een analysis and actual measurement. The top right plot is the measured force and measured velocity times impedance. The bottom right plot is resistance distribution and force in the pile versus depth plot. Analysis of Skin Friction and End Bearing Resistances Driven pile capacity is the sum of the end bearing and skin fricti on. Total capacity is important to the overall structural performance. When scour is possible, however, part of the skin resistance must be ignored when evaluating the pile performance. Currently PDA data are used in a CAPWAP analysis to determine the tip resistance. It is expected that the instrumentation at the tip of the pile provided by the EDC system will allow a better estimate of the end bearing portion of the total pile capacity. This sect ion compares the results of the PDA CAPWAP analysis with that of the EDC results. Table 7-5 shows the results of the EDC and CAPWAP analys is of the piles in which the EDC data collection was successful. The pile capacities calculated using UF method were used for this comparison. CAPWAP predicts average of 16% lower static skin resistance than EDCs predictions on all the operational piles ( Figure 7-16). However, CAPWAPs st atic tip an d total resistances are very close to EDCs predictions ( Figure 7-17 and Figure 7-18 ). It is not known what causes the variations in the static sk in resistance predictions.

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62 An example of the possible variations in CAPWAP analyses is given in Figure 7-19 and Figure 7-20 Figure 7-19 is the first page of CAPWAP analys is output for bent 4 pile FA blow #300. The output shows a total capacity of 1220 kips with skin and tip resistances of 376 kips and 844 kips, respectively. The m atch quality nu mber for this analysis is 2.83 which is an acceptable number. Figure 7-20 is another CAPWAP analysis for the same pile and blow num ber with match quality numbe r of 2.85. Note that the total capacity is 1212 kips with skin and tip resistances of 488 kips and 723 kips, resp ectively. The EDC tip resistance for this pile and blow is 856 kips. As me ntioned before, EDC tip resistance was used as the starting end bearing in the CAPWAP analysis Analysis output shown in Figure 7-20 was obtained using the EDC tip resistance as staring end bearing. This exam ple shows that different combination of skin and tip resistances can achieve similar ma tch quality result. When EDC data are not available to any operator perfor ming the CAPWAP analysis, it is recommended to estimate the tip resistance based on the actual boring log us ing FB-Deep or other pile capacity estimating software before conducting the analysis. Then, use this estimated tip resist ance as the staring tip resistance in CAPWAP analysis. Table 7-6 shows the CW/EDC of the average static skin, tip, and total resistances for the 10 CAPWAP analyses conducted on the Key Royale Bridge Piles. Two blows were selected from each of five piles with operational EDC in this project. For comparison, Table 7-7 shows the CW /EDC of average static sk in, tip, and total resistances fo r 52 CAPWAP analyses from the FDOT database using piles di stributed around the State. CAPWAP predicts very similar total static re sistance and static tip resistance to EDC for both the Key Royale piles and those from the FDOT database. The coefficients of variation for all predictions, however, are higher for the FDOT da tabase than that of the Key Royale piles.

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63 This difference is attributed to the difference in analysis techniques. The CAPWAP analysis of the Key Royale piles was conducted using the EDC tip resistance as a starting point for end bearing. This results in a be tter match between the CAPWAP and EDC tip resistances, thus reducing the scatter. As mentioned before, the FDOT database values were based on blind study, in which the EDC data were not available to the consultant conducting the CAPWAP analysis. Table 7-6 also shows that averaged CAPWAPs pred ic tions of static skin friction are 15% lower than the EDCs predictions. This does not agree with the summary table from database ( Table 7-7 ), but mean CW/EDC skin resistance ratio of 0.85 fall within the database value. The m ean and median CW/EDC skin resistance rati os from database are 1.29 and 0.77, respectively. This indicates that the data is scatter, which is also reflected in the high STD and COV values. In summary, EDCs prediction on the total st atic pile capacity is similar to PDAs prediction. However, EDC predicts significant higher stresses in the pile than PDA, particularly in compressive stress at the bottom of the pile (CSB ). The discrepancies are still to be resolved. EDCs predictions on the total static pile capaci ty and tip resistance are similar to CAPWAPs predicted static total capacity and tip resistance. However, there are some discrepancies in the skin resistances. A possible variatio n in CAPWAP analyses is given in Figure 7-19 and Figure 7-20. W hen comparing the results from this project to the results from database, the results from database have more variations in tip and skin resistances. Again, this variation can due to the method of conducting the CAPWAP and EDC analyses, which is de scribed earlier in the paper.

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64 Table 7-1. All the invalid piles with its malfunctioned EDC parts Pile Status Bent 3 pile UFA Operational Bent 3 pile FA Operational Bent 3 pile SF Operational Bent 3 pile BFS Operational Bent 3 pile MET Water ingress into accelerometers Bent 4 pile UFA Water ingress into accelerometers Bent 4 pile FA Operational Bent 4 pile SF Late acquisition trigger Bent 4 pile BFS Malfunctioned radio Bent 4 pile MET Malfunctioned toe gauges Table 7-2. Summary table of P DA/EDC stresses and capacity ratio PDA/EDC CSX TSX CSB EMX Mean 1.20 1.19 1.24 0.98 Median 1.20 1.22 1.30 0.98 STD 0.09 0.24 0.18 0.06 COV 0.08 0.21 0.15 0.06 Table 7-3. Descriptions of labels Label Description CSX Maximum compressive st ress at top of pile TSX Maximum calculated tensile at top of pile CSB Maximum compressive stress at bottom of pile EMX Maximum case capacity of pile STD Standard deviation COV Coefficient of variance Table 7-4. Summary table of FDOT pile database PDA/EDC CSX TSX CSB EMX Mean 1.10 1.07 1.46 1.09 Median 1.11 1.05 1.32 1.06 STD 0.08 0.30 0.40 0.14 COV 0.07 0.28 0.27 0.13

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65 Table 7-5. Comparison of ED C and CAPWAP skin, tip, and total resistances in kips Pile Blow Analysis Capacity (kips) Skin End Total Bent 3 pile UFA 151 EDC 590 622 1211 CAPWAP 489 666 1151 159 EDC 586 616 1202 CAPWAP 504 629 1133 Bent 3 pile FA 167 EDC 360 577 937 CAPWAP 323 610 933 177 EDC 363 588 951 CAPWAP 324 603 928 Bent 3 pile SF 225 EDC 306 616 922 CAPWAP 196 632 874 230 EDC 242 675 917 CAPWAP 216 670 921 Bent 3 pile BFS 299 EDC 554 641 1195 CAPWAP 411 680 1091 338 EDC 515 691 1206 CAPWAP 421 687 1107 Bent 4 pile MET 236 EDC 469 808 1277 CAPWAP 480 631 1111 300 EDC 426 856 1282 CAPWAP 376 844 1220 Table 7-6. Summary table of CAPWAP/EDC static tip, skin, and total resistance ratio CAPWAP/EDC Total static resistance Skin static resistance Tip static resistance Mean 0.95 0.85 1.00 Median 0.95 0.87 1.02 Std dev 0.04 0.10 0.08 COV 0.04 0.12 0.08 Table 7-7. Summary table of FDOT pile database CAPWAP/EDC Total static resistance Skin static resistance Tip static resistance Mean 0.94 1.29 0.99 Median 0.96 0.77 1.02 Std dev 0.13 2.47 0.26 COV 0.14 1.92 0.27

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66 Figure 7-1. Pile installation for piles in bents 3 and 4 Figure 7-2. Pile Driving Analyzer (PDA) computer that analyzes and displays the driving data Top of pile Ele. 24 ~ Ele. 9 Sand Clay C asing with dia. 42-in ~20 ft ~28 ft Casing lenght 69 ft Ele. -60 24-in square pile 30-in Auger Drill Water level ( ~ 0 Ele. ) Pile lenght 85' ~ Cutoff Ele. 10 Sand Pile tip Ele. ~61

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67 Figure 7-3. Strain gauges and accelerometers were mounted to surface of the pile at pile top Figure 7-4. One-dimensi onal wave propagation

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68 Figure 7-5. SmartPile Review analy zes and displays the drive data Figure 7-6. Measured force between EDC a nd PDA for bent 3 pile BFS at blow #280 -400 -200 0 200 400 600 800 1000 1200 1400 00.020.040.060.080.10.12 Time (sec)Force (kips) PDA EDC

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69 Figure 7-7. Measured accelerat ion between EDC and PDA for be nt 3 pile BFS at blow #280 Figure 7-8. Calculated particle velocity betw een EDC and PDA for bent 3 pile BFS at blow #280 -100 -80 -60 -40 -20 0 20 40 60 80 00.020.040.060.080.10.12 Time (sec)Acceleration (g) PDA EDC -4 -3 -2 -1 0 1 2 3 4 5 6 00.020.040.060.080.10.120.14 Time (sec)Particle Velocity (ft/sec) PDA EDC

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70 Figure 7-9. Case method pile cap acity between EDC and PDA with Jc of 0.3 for bent 3 pile BFS Figure 7-10. Maximum compressive stress at th e top of pile between EDC and PDA for bent 3 pile BFS 0 200 400 600 800 1000 1200 1400 0100200300400 Blow NumberCapacity (kips) PDA EDC 0 0.5 1 1.5 2 2.5 3 0 100200300400 Blow NumberStress (ksi) PDA EDC

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71 Figure 7-11. Maximum tensile st ress at the top of pile betwee n EDC and PDA for bent 3 pile BFS 0.0 0.2 0.4 0.6 0.8 1.0 1.2 0100200300400 Blow NumberStress (ksi) PDA EDC

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72 Figure 7-12. Page 1 of the CAPWAP analysis table output for bent 3 pile FA blow #166

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73 Figure 7-13. Page 2 of the CAPWAP analysis table output for bent 3 pile FA blow #166

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74 Figure 7-14. Page 3 of the CAPWAP analysis table output for Bent 3 Pile FA blow #166

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75 Figure 7-15. Plotted output of CAPWAP analysis for Bent 3 Pile FA blow #166

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76 Figure 7-16. Relationship between the predicte d CAPWAP skin capacity and EDC skin capacity Figure 7-17. Relationship between the predic ted CAPWAP tip capacity and EDC tip capacity Skin Static Capacity0 100 200 300 400 500 600 0100200300400500600 EDCCAPWAP Tip Static Capacity0 100 200 300 400 500 600 700 800 900 0100200300400500600700800900 EDCCAPWAP

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77 Figure 7-18. Relationship between the predic ted CAPWAP total capacity and EDC total capacity Total Static Capacity0 200 400 600 800 1000 1200 1400 0200400600800100012001400 EDCCAPWAP

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78 Figure 7-19. CAPWAP an alysis output for bent 4 pile FA blow #300

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79 Figure 7-20. CAPWAP output results for bent 4 pile FA blow #300

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80 CHAPTER 8 CORROSION MONITORING It is anticipa ted that corrosion readings on bridge piles and durability segments will be taken each year at the same time of year for the first five years and then approximately every five years throughout the remaining serv ice life of the structure. Since the bridge was completed in May 2007, first set of readings was taken as soon after that as possible which was spring. It is recommended to take the readings in the spring to obtain consistent and comparable results. Corrosion readings include the following: Bridge Piles: external corrosion potential of prestressing strand Bridge Piles: surface resistivity Bridge Piles: corrosion potential be tween steel and tit anium electrodes Bridge Piles: external co rrosion potential of steel and titanium electrodes Bridge Piles: electrical curre nt reading of steel electrodes Bridge Piles: electrical resistance reading of steel and titanium electrodes Durability Segments: external corrosion pot ential of steel and titanium electrodes Durability Segments: corrosion potentia l between steel and titanium electrodes Durability Segments: electrical cu rrent reading of steel electrodes Durability Segments: electrical resistan ce reading of steel and titanium electrodes Corrosion Potential of Prestressing St rands, Steel, and Titanium Electrodes Electrical potential read ings give inf ormation about the natural potentials of the probes. They should remain constant until the onset of corrosion. Once significant change in potential readings is noted and other technical reasons but corrosion occurrence are ruled out, then electrical current should be measured as well. The external corrosion potentials were taken using copper-copper-sulfate surface electrodes which are described in the ASTM C8 76 (1999). To take the external corrosion readings with surface electrode, the lead wire from the prestressing strand or embedded corrosion electrode was connected to the positive termin al of the multimeter. The negative (ground) terminal of the multimeter was connected to th e copper-copper-sulfate electrode. To take the

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81 potential reading between two corrosion electr odes (steel and titanium electrodes) with multimeter, the wire from the titanium electrode in the electrical box was connected to the negative terminal of the multimeter. The positive terminal of the multimeter was connected to the wire from the steel electrode. External surface electrodes are primarily desi gned to be used in the liquid solutions. Therefore pre-wetting the surface and use of sponge in-between the electrode and concrete surface is recommended. Over-soaked sponge also can cause unstable readings; therefore, caution is needed on wetting the sponge. Reading must be taken in the exactly same points throughout the years of monitoring in order to enable direct comparis on between the readings from various years. Therefore, it is crucial to determine these points with highest, possible accuracy. Figure 8-1 shows the orien tation of box and electrodes for each mixtur e. For the readings on the bridge piles, Figure 82 along with Table 8-1 and Table 8-2 show the distance from the botto m of pile cap to each pair of electrodes for each instrumented pile in bent 3 and 4. All these figures and tables can be used together to locate the corrosion electr odes accurately for each specific mixture Figure 8-3 shows the mapping between electrodes a nd wires in the electrical box by color of wire and inlets. The m apping makes easier to measure the potential between the corrosion electrodes. Figure 8-4 also shows the surface electrode contact lo cation when m easuring the external corrosion potential of each individual electrode. Besides taking the natural poten tial readings of embedded corro sion electrodes, the natural surface potential of the prestressing strands shou ld also be taken. During construction of the bridge before the pile cap was placed, wiring was connected to two pr estressing strands in opposite corners and extended through a conduit to a PVC junction box below the pile cap for

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82 each pile in bents 2 through 5 ( Figure 8-5 ). Total of two wires were in each PVC junction box, one from each prestressing strand. The continuity between the wires was confirmed at the time when the initial corrosion readings were taken. The natural potential readings should be taken at every 1 foot increment from the presence of marine growth up to the top of the pile. Figure 8-6 and Table 8-3 show the contact location of surf ace electrode f or each pile. In Figure 8-6, 0 to 7 indicates the locations along each pile where the surface potentials were taken. Locations 7 and 0 are the top of m arine growth and below the pile cap. Since the readings were taken from the presence of marine growth up to the top of pile, the distances between each point from 7 to 1 are 1 foot and the distance between 1 and 0 varies, which are shown in Table 8-3 The initial readings and sec ond readings of surface poten tial of the prestressing strands from the bridge piles are shown in Figure 8-7, Figure 8-8, and Figure 8-9 The initial readings show a typical trend of approxim ately -200mV in the dry region of the pile down to less than 350mV in the tidal region of the piles. The s econd readings show the sa me typical trend as the initial readings, but the magnitude is less nega tive which indicates the moisture content of concrete is decreasing with tim e. According to ASTM Standard Test Method for half-cell potentials8 if corrosion potentials over an area are more negative than -350 mV, there is a greater than 90% probability that prestres sing steel corrosion is occurri ng in that area. If corrosion potentials are more positive than -200 mV, ther e is a greater than 90% probability that no prestressing steel corrosion occurs, and for thos e corrosion potentials between -200 mV and -350 mV corrosion activity is uncertain. This agrees with Veerachai et al. who have found that high moisture content concrete (or in any condition of lack of oxygen) will cause the prestressing steel to show more negative values of corrosion potential s. This indicates that the negative potentials are not necessarily an indication that early co rrosion is occurring.

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83 Initial BFS and UFA readings show an interes ting trend in which the dry concrete is less negative that the other piles while the wet concrete areas are more negative than that of the other concretes. From second set of readings, all the piles have si milar potential except FA has the most negative potential over th e dry concrete area and SF show s the similar trend as BFS and UFA in the initial readings. Also, all the readings are more positive than the initial readings which indicate that the moisture content of conc rete has decreased since the initial readings. Over the dry concrete area, reading 0, 1, and 2 ar e more negative than the reading 3 and 4 for all the pile. This is most likely due to the different c oncrete mixture used in the pile cap that affected the readings near top of the pile. For the readings on the durability segments, Figure 8-10 shows the locations of the electrodes and mapping of wires and electrodes. Figure 8-11 and Table 8-4 show the contact location of the surface electrod e when measuring the external potentials of each electrode. The procedures of taking the extern al potential readings and poten tial between electrodes are the same as for the bridge piles described above in the bridge pile sect ion. Before taking the readings, two wires connecting th e steel electrodes need to be removed. Steel electrodes are connected to ensure the same rate of corrosion when corrosion occurs. Since the central and bottom pair of embedded corrosion electrodes were designed to be in the splash zone and completely submerged in the water and the exte rnal surface electrode can not be used in the water, the external potential readings for central and bottom pair of electrodes were taken at water level instead of location of the electrodes. The distance fr om top of the segment to the external surface electrode cont act locations are shown in Table 8-4. Finally, the connection wires need to be placed back to its o riginal positions after taking the readings. It is important to

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84 take external potential readings at exact same location over th e years to obtain comparable results. Surface Resistivity Since the co nductivity of a concrete is relate d to its permeability and diffusivity of ions through the concrete, the electri cal resistance can be used as an estimation of chloride ion penetrability. Surface resistivity test is non-destructive test that measures the electrical resistivity across the face of a concrete to prov ide an indication of its permeability. As the surface resistance increases, the correlated pe rmeability decreases. The use of SCM will typically lower the permeability of the concrete which results in an increase in the surface resistivity. The surface resistivity readings were taken using a Surface Resistivity meter with a Wenner linear four-probe array with inter-probe sp acing of 2-in on one surface of the pile at one foot increments from the presence of ma rine growth up to the top of the pile (Figure 8-12 ). The contact location of surface resistivity reading for each bridg e pile is same as the location of natural potential reading The initial and second readings from the bridge piles are shown in Figure 8-13 Figure 814, and Figure 8-15 Table 8-5 shows the pile casting schedule for all the mixtures. Initial readings show the UFA m ixture has much higher resistivity reading than the other mixtures. Since the UFA and FA piles were constructed appr oximately three to four months earlier than other piles, UFA may have had a significantly higher SR values th an other mixtures at the time when the initial readings were taken. However, UFA had higher SR values than FA. This is attributed to the increased fineness of th e UFA making concrete less permeable. Second readings show significant increased SR values of SF and BFS mixtures and the UFA mixture still has the highest SR value among all other mixtures Similar to the labo ratory testing results

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85 ( Figure 4-11 ), SF and BFS had higher SR values than FA and MET at the age tha t the initial and second readings were taken. Electrical Resistance of Steel and Titanium Electrodes Electrical resistan ce is measured to ensure there is not any direct contact between the steel and titanium electrodes at each lo cation. If there is a path or direct connection, the current or potential readings between the el ectrodes would not be valid. Electrical resistance was measured using both the Nilsson AC current resistance meter and the Fluke DC current multimeter. Initial resistance readings should be high which indi cates there is not any connection between the electrodes. If the resistance readings become lower in the future, it would be an indication that chlorides may have penetrated the concrete and making it more conductive If the resistance becomes higher in the future, it woul d be an indication of bad wires. Electrical resistance is also measured to develop a correction factor for th e current readings. T ypically, current reading between the electrodes is in microamp scale. On this scale, the internal resistance of the meter is very high which would alter th e current reading. The correction factor can be calculated from measured resistance between the electrodes a nd internal resistance of the meter. Electrical Current of Steel Electrodes Currents readings should be taken after the ch ange of potential m easurements is observed, which indicates corrosion activity. Surface area of each steel probe is constant as well as titanium, so the corrosion density current can be determined. Because of the specific surface area of the probes, potentiostatic linear polarization test can be used to measure the corrosion rate and determine the corrosion intensity.

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86 Table 8-1. Location of corrosion elect rodes in 24-in FA and UFA piles A B C FA3 61.5-in 85.5-in 12-in UFA3 59-in 83-in 12-in FA4 53.5-in 77.5-in 12-in UFA4 55.5-in 79.5-in 12-in Table 8-2. Location of corrosion electro des in 24-in SF, BFS, and MET piles D E F SF3 65-in 89-in 12-in MET3 48.5-in 72.5-in 12-in BSF3 60.5-in 84.5-in 12-in SF4 50-in 74-in 12-in MET4 56.6-in 80.5-in 12-in BSF4 56-in 80-in 12-in Table 8-3. A dimension for surface resistiv ity and external potential measurements Bent Pile UFA FA SF MET BFS 2 7 6.5 12 6.5 7 3 8.5 7 12 6 6 4 12 12 12 12 12 5 7.5 7.5 12 7 6.5 Table 8-4. External elec trodes measuring locations Mixture *Distance A (in) measured from top of the segment) S1 R S2 R S3 R T1 R T2 R T3 R CEM 10 16 16 10 16 16 UFAF 10 16 16 10 16 16 FAF 10 16 16 10 16 16 SFF 9 18 18 9 18 18 METF 10 19 19 10 19 19 BFSF 10 19 19 10 19 19 Table 8-5. Pile casting schedule Mixture Pile Cast Date UFA 6/6/2006 FA 6/23/2006 SF 9/29/2006 BFS 10/6/2006 MET 10/13/2006

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87 Figure 8-1. The orientation of box and electrodes for each mixture Figure 8-2. Location of corrosion probes relative to the bottom of pile cap in the 24-in piles 3 4 UFA FA SF MET BFS AA BB CC DD PHASE 1 PHASE 2 NORTH VIEW BB VIEW AA VIEW CC Electrodes Box A B C C Pile Cap Pile Cap VIEW DD E D F F Pile Cap Pile Cap Box Electrodes

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88 Figure 8-3. The mapping between electrodes and wire s in the electrical b ox by color of wire and inlets Figure 8-4. The surface electrode contact loca tion when measuring the external corrosion potential of each individual electrode White (Layer 1 Titanium) Yellow (Layer 1 Steel) Black (Layer 2 Steel) White (Layer 2 Titanium) Layer 1 Layer 2 Steel 1, S1Steel 2, S2 Titanium 1, T1Titanium 2, T2 Electrical Box Yellow Black White

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89 Figure 8-5. Locations of electr ical boxes on th e bridge pile Figure 8-6. Surface resistivity and external potentials measuring locations 0 1 2 3 4 5 7 6 Pile Cap Bridge Pile A 8In Water 7 sp. @ 1'-0"

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90 Figure 8-7. Initial electrical po tential reading taken on 5/8/2007 Figure 8-8. Initial electrical po tential reading taken on 6/26/2007 0 1 2 3 4 5 6 7 8 -600 -500 -400 -300 -200 -100 0 Electrical Potential (mV)Pile Depth (ft) UFA FA SF BFS MET -200 mV-350 mV 0 1 2 3 4 5 6 7 8 -600 -500 -400 -300 -200 -100 0 Electrical Potential (mV)Pile Depth (ft) UFA FA SF BFS MET -200 mV-350 mV

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91 Figure 8-9. Second electrical pot ential readings taken on 06/29/08 0 1 2 3 4 5 6 7 8 -600 -500 -400 -300 -200 -100 0 Electrical Potential (mV)Pile Depth (ft) UFA FA SF BFS MET -200 mV-350 mV

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92 Figure 8-10. Location and mapping of wires and electrodes in the durability segment Steel (yellow) Titanium (white) Electrical Box Steel (magenta) Titanium (white) Steel (Black) Titanium (white) 9" 1' 9" 1' 9" 9" White (Titanium) Yellow (Steel) White (Titanium) Magenta (Steel) White (Titanium) Black (Steel) Thermocouple wires

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93 Figure 8-11. Potential readings ex ternal electrode contact locations Figure 8-12. Wenner linear f our-probe array and display Steel 1, S1(yellow) Titanium 1, T1(white) Electrical Box Steel 2, S2(magenta) Titanium 2, T2(white) Steel 3, S3(Black) Titanium 3, T3(white) A External Electrode

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94 Figure 8-13. Initial surface resi stivity reading taken on 5/8/2007 Figure 8-14. Initial surface resi stivity reading taken on 6/26/2007 0 1 2 3 4 5 6 7 8 050100150200250300350 Surface Resistivity (k-ohms)Pile Depth (ft) UFA FA SF BFS MET 0 1 2 3 4 5 6 7 8 050100150200250 Surface Resistivity (k-ohms)Pile Depth (ft) UFA FA SF BFS MET

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95 Figure 8-15. Second surface resistivity reading taken on 6/29/2008 0 1 2 3 4 5 6 7 8 050100150200250300 Surface Resistivity (k-ohms)Pile Depth (ft) UFA FA SF BFS MET

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96 CHAPTER 9 SUMMARY AND CONCLUSIONS This paper d escribes the implementation of highly reactive supplementary cementitious materials into the construction of the Key Roya le Bridge. Six different SCM were used to construct the bridge and fender piles to allow monitoring under realistic exposure conditions at real time rather than accelerated corrosion testing in laborato ry conditions. Corrosion sensors were embedded in the bridge piles for periodic monitoring over several years. Removable fender piles were also installed with the same mixt ures and will be removed in 15-20 years to be examined for ingress of chlorides and corrosion damage. In addition, durability segments were also constructed using the same concrete and pr estressing strand as the fender piles. These segments were hung from the fender piles for cons istent exposure conditions and instrumented with corrosion sensors and temperature sensors for long-term corrosion and temperature monitoring. These segments will also be cored for evaluating the chloride ion penetration and concrete hydration over time. Embedded Data Co llectors (EDCs) were also installed in the bridge piles for monitoring pile driving. Reduced strain and acceleration, pile driving stresses, and static pile capacities collected from EDC were compared to the data collected from the conventional monitoring system, Pile Drivi ng Analyzer (PDA). CAPWAP analyses were performed on PDA data to separate the skin and tip resistances. The results of CAPWAP analyses were also compared to the EDCs resu lts. The benefits of this project include improving longer durability of bridge piles, allowing use of alternative SCM in bridge pile construction, allowing future corrosion and te mperature monitoring, and evaluating the use of new pile driving monitoring system (E DC). Conclusions are as follows: Second set of surface potential read ings are more positive than the first set of readings as moisture content of the concrete decreases since the first set of readings. All the mixtures have similar readings except FA, whic h has the most negative reading.

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97 First and second sets of surf ace resistivity readings on bri dge piles are similar to the laboratory testing results. UF A has the highest SR values, followed by BFS and SF. FA and MET have the lowest SR values. EDC predicts average of 20% higher compre ssive and tensile stresses than PDAs predications. It is not known what causes these significant differences in stresses. However, EDCs predictions on fixed Jc pile capacity are similar to PDAs fixed Jc capacity. EDCs predictions on static end b earing and total pile capacity ar e similar to the results from CAPWAP analyses. The differences are within 5%. However, skin friction predicted from CAPWAP analyses are average of 15% higher than the skin friction from EDC. An example has shown that different combination of skin and tip resistances can achieve similar match quality result. This can be a possible cau se of variations in CAPWAP analyses. CAPWAP predicts very similar total static resi stance and static tip resistance to EDC for both the Key Royale piles and those from the FDOT da tabase. The coefficients of variation for all predictions, however, are higher fo r the FDOT database than that of the Key Royale piles. This difference is attributed to th e difference in analysis techniques.

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98 LIST OF REFERENCES ACI Comm ittee 363, 1992. State-of-the-Art Repo rt on High-Strength Conc rete (ACI 363R-92) (Reapproved 1997), American Concrete Institute. ASTM C876-91, 1999. Standard Test Method for Half -Cell Potentials of Uncoated Reinforcing Steel in Concrete, American So ciety for Testing and Materials. Buil, M. and Acker, P., 1985. Creep of a silica fume concrete, Cement and Concrete Research, V. 15, No. 3, 463-466. Clough, Ray W. and Penzien, J., 1975. Dynamics of structures, 2nd edition, McGraw-Hill, New York, 364-381. FM5-578 (2004), Concrete Resistivity as an Elec trical Indicator of Permeability. Florida Department of Transportation (FDOT). Herrera, R, 2008. EDC Evaluation Phase I, Geotechnical Research In Progress (GRIP), Florida Department of Transportation. Lohtia, R.P., Nautiyal, B.D., and Jain, O.P., 1976. Creep of fly ash concrete, Journal of The American Concrete Institute, V 73, No. 8, 469-472. NT BUILD 492, 1999. Concrete, mortar and cement-bas ed repair materials: Chloride Migration Coefficient from Non-Stea dy-State Migration Experime nts, Nordtest Method. Pile Dynamics, Inc., 2006. Case pile wave analysis program CAPWAP background, Pile Dynamics, Inc., Cleveland, Ohio. Roske, Edward K., 2007. Implementation of highly reactive pozzolans in th e Key Royale bridge replacement, M.S. Thesis, University of Florida. Veerachai, L., Kyung, Je-W., Masayasu, O., a nd Masaru Y., 2004. Analysis of half-cell potential measurement for corrosi on of reinforced concrete, Construction and Building Materials, V. 18, No. 3, 155-162. Zhang, L., McVay, Michael C., and Ng, Charles W.W., 2001. A possible physical meaning of Case damping in pile dynamics, Canadian Geotechnical Journal, Vol. 28, No. 1, 83-94.

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99 BIOGRAPHICAL SKETCH Yen-Chih Tsai was born on 1982 in Taipei, Taiw an, to Ching and Jung Tsai. He graduated from South-Dade Senior High School in Miam i, Florida in May of 2001. He received his Associate of Arts degree in August of 2003 from the Miami-Dade Community College in Miami, Florida. He transferred to the University of Fl orida for his bachelors degree. He received Bachelor of Science degree in civil engineering in Decembe r 2005. After his graduation, YenChih worked as an Engineer Intern at HNT B Corp. from February of 2006 to August of 2006, Yen-Chih continued his education by entering gra duate school to pursue a Master of Science in the Structural Group of the Civil and Coastal Engineering Depart ment at the University of Florida in the August 2002. He received his Mast er of Science in the December of 2008.