Citation
Relationship Between Laboratory Mix Properties and Rutting Resistance for Superpave Mixtures

Material Information

Title:
Relationship Between Laboratory Mix Properties and Rutting Resistance for Superpave Mixtures
Creator:
Asiamah, Sylvester Ampadu
Copyright Date:
2008

Subjects

Subjects / Keywords:
Analyzers ( jstor )
Asphalt ( jstor )
Asphalt pavements ( jstor )
Construction aggregate ( jstor )
Gyration ( jstor )
Pavements ( jstor )
Ruts ( jstor )
Specimens ( jstor )
Transportation ( jstor )
Wheels ( jstor )
Genre:
bibliography ( marcgt )
theses ( marcgt )
government publication (state, provincial, terriorial, dependent) ( marcgt )
born-digital ( sobekcm )
Electronic Thesis or Dissertation
Civil and Coastal Engineering thesis, M.E.

Notes

Abstract:
Various pavement sections within the State of Florida were selected and used in a joint research program by the Florida Department of Transportation (FDOT) and the University of Florida for a comprehensive monitoring of field performance of Superpave mixtures. These pavement mixes had been designed in accordance with the Superpave procedure, using varied sources of aggregates for each project and constructed by different contractors. Analysis of available data gathered within the first two years of construction of these pavements indicated that two of the pavements exhibited relatively poor rutting performance. Further investigations using falling weight deflectometer to test the adequacy of the foundation and evaluation of core samples of the top layer suggested that the poor performance of these mixtures might be related to poor mix quality of these two Superpave mixtures. Six of these FDOT mixtures were selected and their design job mix formulas reproduced in the laboratory, but without the Reclaimed Asphalt Pavement (RAP) material, which was part of the original blend of aggregates. The new blends were also designed using the Superpave volumetric mix design procedure. Samples of these laboratory-reproduced mixtures were then tested, to evaluate their rutting resistance or shear properties, in the Servopac Gyratory Compactor, Asphalt Pavement Analyzer (APA) and the Gyratory Testing Machine (GTM). Analyses of test results in this study indicate that excessive asphalt binder may have been used in order to meet the voids in mineral aggregates (VMA) criteria for the poor performing mixtures. This finding may be consistent with other related findings that suggest that for some coarse graded aggregate structures, addition of so much asphalt binder may be necessary to meet the current Superpave VMA specification. The VMA requirement should, therefore, be reviewed. It is also found in this study that for mixtures with excessive asphalt binder the aggregate structure may not significantly affect the rutting resistance of the mixture. This may be the case because the asphalt binder tends to have a predominant influence, especially at higher temperatures, reduces the aggregate particle interaction in the mixture and, therefore, leads to poor rutting performance. The study finds that there may be apparent relationships between rutting resistance of mixtures and the following laboratory measured parameters: (1) the rate of change of gyratory shear per cycle measured from the slope of the gyratory shear versus number of cycles (semi-logarithm scale) in the Servopac Gyratory Compactor, (2) the rut depth measured in the Asphalt Pavement Analyzer and (3) the gyratory stability index measured from the Gyratory Testing Machine. ( English )

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Source Institution:
University of Florida
Holding Location:
University of Florida
Rights Management:
Copyright the Sylvester Ampadu Asiamah. Permission granted to the University of Florida to digitize, archive and distribute this item for non-profit research and educational purposes. Any reuse of this item in excess of fair use or other copyright exemptions requires permission of the copyright holder.
Embargo Date:
5/4/2002
Resource Identifier:
51740353 ( OCLC )

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RELATIONSHIP BETWEEN LABORATORY MIX PROPERTIES AND RUTTING RESISTANCE FOR SUPERPAVE MIXTURES By SYLVESTER AMPADU ASIAMAH 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 ENGINEERING UNIVERSITY OF FLORIDA 2002

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ACKNOWLEDGMENTS The author wishes to express his appreciation to his advisor and committee chair Dr. Mang Tia, for offering him guidance and support throughout his program of study at the University of Florida and for being instrumental in the completion of this research study. He would also like to express appreciation to his committee co-chair, Dr. Reynaldo Roque, and committee member, Dr. Yusuf Mehta, for their advice and technical support that they willingly offered him while undertaking this study. The Florida Department of Transportation (FDOT) is acknowledged with gratitude by this author for providing funding, technical support and the use of their materials laboratory for this research. Special thanks go to Susan J. Andrews and Frank Suarez as well as other FDOT materials office personnel for their help. The Civil Engineering Laboratory Manager of the University of Florida, Mr. George Lopp, is greatly appreciated for his time and technical guidance. Daniel Darku, Dr. Bensa Nukunya, Claude Villiers and all graduate students in the Civil Engineering Materials Group at the University of Florida have been very supportive in the progress and completion of this research and are very much acknowledged with gratitude by the author. Finally, the author wishes to give his utmost thanks and gratitude to his family and friends for giving him their unflinching support and motivation throughout his entire program of studies at all levels up to this stage. God has been good; to Him be all the glory forever. ii

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TABLE OF CONTENTS page ACKNOWLEDGMENTS..................................................................................................ii LIST OF TABLES.............................................................................................................vi LIST OF FIGURES.........................................................................................................viii ABSTRACT .....................................................................................................................xi CHAPTERS 1 INTRODUCTION...........................................................................................................1 1.1 Background..........................................................................................................1 1.2 Objectives............................................................................................................4 1.3 Scope....................................................................................................................4 1.4 Research Approach..............................................................................................5 1.4.1 Phase I....................................................................................................5 1.4.2 Phase II...................................................................................................5 2 LITERATURE REVIEW................................................................................................7 2.1 Introduction..........................................................................................................7 2.2 Permanent Deformation.......................................................................................7 2.2.1 Types of Rutting.....................................................................................8 2.2.1.1 Rutting by densification................................................................8 2.2.1.2 Rutting by raveling........................................................................9 2.2.1.3 Rutting by shoving........................................................................9 2.2.2 Mixture Properties that Influence Rutting Resistance..........................10 2.3 Superpave Mix Design.......................................................................................11 2.3.1 Material Specifications.........................................................................11 2.3.2 Method of Compaction.........................................................................12 2.3.4 Mixture Design.....................................................................................13 2.3.5 Shortfalls of the Superpave Mix Design..............................................13 2.4 Mixture Performance Testing............................................................................15 2.4.1 Servopac Gyratory Compactor.............................................................17 2.4.2 Asphalt Pavement Analyzer.................................................................18 2.4.3 Gyratory Testing Machine....................................................................19 iii

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3 MATERIALS AND TESTING METHODS.................................................................20 3.1 Introduction........................................................................................................20 3.2 Materials............................................................................................................21 3.2.1 Aggregates............................................................................................21 3.2.2 Asphalt Binder......................................................................................22 3.3 Mixture Design..................................................................................................22 3.3.1 Aggregate Preparation and Batching....................................................22 3.3.2 Mixing..................................................................................................23 3.3.4 Short Term Oven Aging (STOA).........................................................23 3.3.5 Compaction..........................................................................................28 3.4 Servopac Gyratory Compactor..........................................................................29 3.5 Asphalt Pavement Analyzer Testing Procedure................................................31 3.6 Gyratory Testing Machine Procedure................................................................34 4 SUMMARY AND ANALYSES OF TEST RESULTS................................................38 4.1 Introduction........................................................................................................38 4.2 Field Rutting......................................................................................................39 4.3 Servopac Gyratory Compactor Results..............................................................40 4.3.1 Gyratory Shear.....................................................................................41 4.3.2 Gyratory Shear and Air Voids..............................................................42 4.4 Asphalt Pavement Analyzer (APA) Results......................................................43 4.5 Comparing APA Rutting and Field Rutting.......................................................51 4.6 Gyratory Testing Machine (GTM) Results........................................................53 4.6.1 Gyratory Stability Index (GSI).............................................................54 4.6.2 Comparing Gyratory Stability Index and Field Rutting.......................54 4.7 The Superpave VMA Criteria and Mixture Rutting Performance.....................55 4.8 Aggregate Gradation Effects..............................................................................61 4.9 Predicting Rutting Performance of Mixtures.....................................................63 4.9.1 The Rate of Change of Gyratory Shear With Cycles from Servopac..65 4.9.2 Asphalt Pavement Analyzer (APA) Rut Depth....................................67 4.9.3 Gyratory Testing Machine (GTM) Stability Index..............................67 5 CONCLUSIONS............................................................................................................70 5.1 Overview............................................................................................................70 5.2 Summary of Findings.........................................................................................70 5.3 Recommendations..............................................................................................72 iv

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APPENDICES A AGGREGATE GRADATIONS, PROPERTIES AND BATCH WEIGHT SHEETS B MIXTURE VOLUMETRIC PROPERTIES AND CHARACTERISTICS, SERVOPAC AND GTM TEST RESULTS..90 C FIELD DATA: FALLING WEIGHT DEFLECTOMETER AND RUT DEPTHS....99 REFERENCES................................................................................................................105 BIOGRAPHICAL SKETCH...........................................................................................110 v

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LIST OF TABLES Table Page 3-1: Selected Pavements and Locations.................................................................................20 3-2: Aggregate Sources for Selected FDOT Mixtures...........................................................24 3-3: Aggregate Sources and Modify Blends for Research Mixtures.....................................25 4-1: Field Rutting Data..........................................................................................................39 4-2: APA Specimen Properties and Rut Depths....................................................................50 4-3: Properties for Mix #1 and Mix #5 at N des .......................................................................55 4-4: Comparing Test Results for Mixture #1-A and #1-B.....................................................60 4-5: Comparing Test Results for Mixture #5-A and #5-B.....................................................61 4-6: Comparing Test Results for Mixture #M1 and #1..........................................................61 4-7: Comparing Field and Laboratory Performance..............................................................65 A-1: Gradations and Specific Gravity of Aggregates for Project #1.....................................75 A-2: Gradations and Specific Gravity of Aggregates for Project #2.....................................75 A-3: Gradations and Specific Gravity of Aggregates for Project #3.....................................76 A-4: Gradations and Specific Gravity of Aggregates for Project #5.....................................76 A-5: Gradations and Specific Gravity of Aggregates for Project #7.....................................77 A-6: Gradations and Specific Gravity of Aggregates for Project #8.....................................77 A-7: Summary of Design JMF and Reproduced Blend of Aggregate Gradations................78 A-8: Cumulative Batch Weight for Project #1......................................................................85 A-9: Cumulative Batch Weight for Project #2......................................................................86 A-10: Cumulative Batch Weight for Project #3....................................................................87 vi

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A-11: Cumulative Batch Weight for Project #5....................................................................88 A-12: Cumulative Batch Weight for Project #7....................................................................89 B-1: Mixture Volumetric Properties and Compaction Characteristics..................................91 vii

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LIST OF FIGURES Figures Page 3-1: 9.5 mm-Nominal Maximum Size Gradations (Projects 1 & 5)......................................26 3-1: 12.5 mm-Nominal Maximum Size Gradations..............................................................27 3-3: Pine Gyratory Compactor...............................................................................................29 3-4: Servopac Gyratory Compactor.......................................................................................32 3-5: Asphalt Pavement Analyzer (APA)................................................................................35 3-6: Gyratory Testing Machine (GTM).................................................................................37 4-1: Field Rut Depth per ESALs............................................................................................40 4-2: Gyratory Shear vrs Number of Cycles for 1.25 Degrees in the Servopac......................44 4-3: Gyratory Shear vs Number of Cycles for 2.5 Degrees in the Servopac.........................45 4-4: Gyratory Shear vrs Log of Cycles for Gyrations Between Air Voids of 7%-4%..........46 4-5: Gyratory Shear vrs Air Voids at 1.25 Degrees in the Servopac.....................................47 4-6: Percent G mm vs Number of Cycles for 1.25 Degrees in the Servopac............................48 4-7: Percent Air Voids vs Number of Cycles for 1.25 Degrees in the Servopac...................49 4-8: APA Rut Depth For 8000 Wheel Strokes.......................................................................50 4-9: APA Rut Depth vs Number of Strokes...........................................................................52 4-10: Gyratory Shear vs Number of Cycles in the GTM.......................................................56 4-11: Gyratory Stability Index of the Mixtures.....................................................................57 4-12: Percent AC vs Percent VMA for Mixture #1...............................................................58 4-13: Percent AC vs Percent Air Voids for Mixture #1.........................................................59 4-14: Percent AC vs Percent VFA for Mixture #1................................................................59 viii

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4-15: Percent AC vs Percent VMA for Mixture #5...............................................................62 4-16: Percent AC vs Percent Air Voids for Mixture #5.........................................................62 4-17: Percent AC vs Percent VFA for Mixture #5................................................................63 4-18: Gradation Chart Showing Modified Blend #M1..........................................................64 4-19: Correlation of the G s /log No. of Cycles Measured from Servopac With Field.......66 4-20: Correlation of the APA Rut Depth With Field Rutting................................................68 4-21: Correlation of the GTM Gyratory Stability Index With Field Rutting........................69 A-1: Gradation Chart for JMF and Blend of Project No. 1. (9.5mm Nominal size).............79 A-2: Gradation Chart for JMF and Blend of Project No. 2. (12.5mm Nominal size)...........80 A-3: Gradation Chart for JMF and Blend of Project No. 3. (12.5mm Nominal size)...........81 A-4: Gradation Chart for JMF and Blend of Project No. 5. (9.5mm Nominal size).............82 A-5: Gradation Chart for JMF and Blend of Project No. 7. (12.5mm Nominal size)...........83 A-6: Gradation Chart for JMF of Project No. 8. (12.5mm Nominal size).............................84 B-1: Gyratory Shear vs Number of Cycles for Servopac Compaction at 1.25 Degrees........92 B-2: Gyratory Shear vs Number of Cycles for Servopac Compaction at 2.5 Degrees..........93 B-3: Percent G mm vs Number of Cycles for Servopac Compaction at 2.5 degrees...............94 B-4: Gyratory Shear vs Percent Air Voids for Servopac Compaction at 2.5 Degrees..........95 B-5: Percent Air Voids vs Number of Cycles for Servopac Compaction at 2.5 degress.......96 B-6: Percent G mm vs Number of Cycles for Compaction in GTM........................................97 B-7: Percent Air Voids vs Number of Cycles for Compaction in GTM...............................98 C-1: FWD Measurements at 30 Locations for Project #1......................................................100 C-2: FWD Measurements at 30 Locations for Project #2......................................................100 C-3: FWD Measurements at 30 Locations for Project #3......................................................101 C-4: FWD Measurements at 30 Locations for Project #5......................................................101 C-5: FWD Measurements at 30 Locations for Project #7......................................................102 ix

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C-6: Field Rut Depths Measured at 30 Locations on Project #1...........................................102 C-7: Field Rut Depths Measured at 30 Locations on Project #2...........................................103 C-8: Field Rut Depths Measured at 30 Locations on Project #3...........................................103 C-9: Field Rut Depths Measured at 30 Locations on Project #5...........................................104 C-10: Field Rut Depths Measured at 30 Locations on Project #7.........................................104 x

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Abstract of Thesis Presented to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Master of Engineering RELATIONSHIP BETWEEN LABORATORY MIX PROPERTIES AND RUTTING RESISTANCE FOR SUPERPAVE MIXTURES By Sylvester Ampadu Asiamah May 2002 Chairman: Dr. Mang Tia Cochairman: Dr. Reynaldo Roque Major Department: Civil and Coastal Engineering Various pavement sections within the State of Florida were selected and used in a joint research program by the Florida Department of Transportation (FDOT) and the University of Florida for a comprehensive monitoring of field performance of Superpave mixtures. These pavement mixes had been designed in accordance with the Superpave procedure, using varied sources of aggregates for each project and constructed by different contractors. Analysis of available data gathered within the first two years of construction of these pavements indicated that two of the pavements exhibited relatively poor rutting performance. Further investigations using falling weight deflectometer to test the adequacy of the foundation and evaluation of core samples of the top layer suggested that the poor performance of these mixtures might be related to poor mix quality of these two Superpave mixtures. Six of these FDOT mixtures were selected and their design job mix formulas reproduced in the laboratory, but without the Reclaimed Asphalt Pavement (RAP) xi

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material, which was part of the original blend of aggregates. The new blends were also designed using the Superpave volumetric mix design procedure. Samples of these laboratory-reproduced mixtures were then tested, to evaluate their rutting resistance or shear properties, in the Servopac Gyratory Compactor, Asphalt Pavement Analyzer (APA) and the Gyratory Testing Machine (GTM). Analyses of test results in this study indicate that excessive asphalt binder may have been used in order to meet the voids in mineral aggregates (VMA) criteria for the poor performing mixtures. This finding may be consistent with other related findings that suggest that for some coarse graded aggregate structures, addition of so much asphalt binder may be necessary to meet the current Superpave VMA specification. The VMA requirement should, therefore, be reviewed. It is also found in this study that for mixtures with excessive asphalt binder the aggregate structure may not significantly affect the rutting resistance of the mixture. This may be the case because the asphalt binder tends to have a predominant influence, especially at higher temperatures, reduces the aggregate particle interaction in the mixture and, therefore, leads to poor rutting performance. The study finds that there may be apparent relationships between rutting resistance of mixtures and the following laboratory measured parameters: (1) the rate of change of gyratory shear per cycle measured from the slope of the gyratory shear versus number of cycles (semi-logarithm scale) in the Servopac Gyratory Compactor, (2) the rut depth measured in the Asphalt Pavement Analyzer and (3) the gyratory stability index measured from the Gyratory Testing Machine. xii

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CHAPTER 1 INTRODUCTION 1.1 Background Permanent deformation in asphalt pavements has been a major problem and source of concern in many nations. In recent years researchers in various institutions and organizations are making many attempts to strengthen mix design criteria and quality acceptance procedures to enhance mixture performance. One of such latest attempts led to the development, in 1993, of the Superpave volumetric mix design method by the Strategic Highway Research Program (SHRP). Even though Superpave is currently undergoing evaluation and many State agencies within the United States are vigorously implementing this new method, the problem of premature rutting in pavements still highly persists. It is expected that the completion of the second phase of implementation of Superpave Design System will address this problem through the development of performance prediction tests and models for rutting, fatigue cracking and low temperature cracking, among others. Rutting is the accumulation of permanent deformation primarily caused by instability of the mixture or traffic densification in the top or lower layers or both. It often results in visible channels in the wheelpaths of the roadway. The current Superpave volumetric design criteria partially address the problem of rutting and durability of asphalt mixtures through the use of control points, which are developed to ensure the use of continuous gradations, and the restricted zone, which is to prevent the production of tender mixes. In addition, the aggregates must satisfy the requirements for the aggregate 1

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2 consensus properties. These would be expected to result in mixes with high rut resistance by obtaining a good aggregate structure, but on the contrary, there is enough evidence to suggest that poor mixes are still produced that meet the requirements for VMA (voids in mineral aggregates) while other potentially good mixes are rejected because their gradation pass through the restricted zone. These scenarios have prompted calls for review and modifications in the specifications for Superpave mixtures. The aggregate skeleton for the mixture must be able to carry the traffic load especially in the summer when the temperatures are relatively high, because the viscosity of the binder is low at high temperatures. If the aggregate has a poor structure then rutting is likely to occur at this period. The Superpave volumetric criterion for VMA is currently based only on the nominal maximum size of the aggregates and is independent of the type of gradation. Several studies have shown that some of the current Superpave volumetric criteria should be made dependent on the gradation so as to prevent the use of poorly graded or poorly structured aggregates, because they usually result in mixtures that have low resistance to deformation, yet they may be accepted once the mix meets the VMA and other requirements. There is the need to evaluate gradation parameters to ensure a continuous gradation and also provide tighter gradation guidelines. As mentioned earlier there are, currently, no well-developed performance-based tests and models to adequately predict good and poor performing mixes during design. However, investigations still in progress seems to indicate that some parameters such as the gyratory shear strength measurement obtained from Gyratory Compactors (e.g. Superpave) and the Gyratory Testing Machine may be used as an index to predict rut resistance for Hot-Mix Asphalt (HMA) mixtures in the laboratory. The Superpave

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3 Gyratory Compactor was used in the Superpave design method for compaction of HMA mixes because this device can compact HMA samples to a density similar to that obtained in the field under traffic. It also tends to orient the aggregate particles similar to that observed in the field. The Gyratory Testing Machine, developed by the U.S. Army Corps of Engineers, has also been designed to compact HMA mixes using a gyratory mechanism and is capable of simulating the action of rollers during construction. This device can also monitor the change in mixture response with densification. Therefore, the above two equipments may be used as tools to identify the rutting potential of HMA mixtures. The Asphalt Pavement Analyzer (APA), a version of the Georgia loaded wheel tester, is an accelerated rutting device which has been widely used to measure rut depths of HMA mixtures in the laboratory. The Florida Department of Transportation (FDOT) has used the Georgia loaded wheel tester successfully to test and rank mixtures and it was found to correlate well with the ranking observed by rut depth measurements in the field [1]. Thus this device may also be a useful tool for laboratory identification of the rutting resistance of HMA mixtures. This study evaluates the field rutting performance of some different Superpave pavement sections constructed in the State of Florida. The field rutting performance of these mixes are correlated with laboratory test and analysis of results obtained from (1) Servopac Gyratory Compactor, which is a model of the Superpave Gyratory Compactor, (2) Gyratory Testing Machine and (3) Asphalt Pavement Analyzer.

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4 1.2 Objectives The main objectives of this study are To evaluate the rutting performance of some selected Superpave projects To identify the possible causes of rutting for poor performing mixtures To identify which mixture design parameters are closely related to mixture rutting performance. To investigate the possibility of using certain measurable parameters from (1) Servopac Gyratory Compactor (2) Gyratory Testing Machine and (3) Asphalt Pavement Analyzer as a tool for predicting rut performance. Which of these three equipments gives reliable result that correlates well with field performance? 1.3 Scope In this study, a comprehensive evaluation of six Superpave roadway sections are undertaken to find the causes of their relative field rut performances. The projects selected cover a broad range of contractors and materials that are approved and widely used in the State of Florida. Approximately, five-mile sections on each of the highways were evaluated; core samples and rut depth measurements were taken within the first two years after construction at thirty locations along these sections. Falling weight deflectometer tests were also conducted at all thirty locations to assess the adequacy of the foundations of these roads. Laboratory tests were conducted on the Superpave layers obtained from the cores and then some of the mixtures had their designed job mix formulas (JMF) reproduced, mixed and tested to evaluate the effects of their mix properties on observed rutting performance.

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5 1.4 Research Approach The study aimed at assessing the performance of selected projects in Florida. The research approach for the first and second phases of the project are given below: 1.4.1 Phase I Measure rut depths at thirty locations selected for each project and take core specimens at these locations for laboratory analysis of volumetric properties. Compare the rutting performance of the Superpave mixtures and evaluate their rut depths and rate of increase of rutting per million ESALs between the projects. Conduct falling weight deflectometer tests and backcalculation on each project’s thirty locations to determine the effective modulus of all layers along the project and to identify the problems within the pavement system [2]. To identify any variations of in-place volumetric properties (air voids, asphalt content and gradation) of the Superpave layers along the pavement sections as measured from the core samples and also using data from the quality control (QC), quality assurance (QA), and independent assurance (IA). To evaluate the effects of variations of in-place volumetric properties on rut performances of the pavements for these selected projects. Based on the above analysis, develop a hypothesis for the causes of rutting and for the variable field rut performances between projects. 1.4.2 Phase II The second phase, which is the main task of this study, is to verify a hypothesis for the possible causes of defects that are contributing factors for the poor performance of failing projects. This was approached under the following guidelines: Reproduce the design JMF of the mixtures in the laboratory by o Keeping the same gradations and aggregate sources but without the RAP, which was no longer available. o Determining design asphalt contents for the mixes to satisfy all Superpave criteria.

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6 Test the mixes in the Servopac Gyratory Compactor, Gyratory Testing Machine (GTM) and the Asphalt Pavement Analyzer (APA). Correlate the gyratory shear obtained from the Servopac and the GTM with the field rut performance data. Also correlate the rut depth results of the APA with that of the field. Conduct a simple statistical analysis to correlate measured parameters with rutting performances of the mixtures.

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CHAPTER 2 LITERATURE REVIEW 2.1 Introduction The subject of permanent deformation in HMA pavements has generated a lot of concern and as a result much research has been done in this area. More research is still going on in many institutions and agencies. All attempts are geared towards improving mixture quality and performance. This is being done through the identification of mixture design parameters that directly or indirectly relate to performance so that they can be effectively controlled to obtained durable pavements. Lately, the focus is shifting gradually to cover also the establishment of performance-based laboratory test methods and models to accurately predict mixture performance beforehand. The development and subsequent adoption of the Superpave Volumetric Design Method, in 1993, is one of the many attempts to improve HMA mixture performance. This chapter reviews some of the literature available on the subject matter regarding this study. The causes of permanent deformation, mixture-design parameters affecting rut performance and test methods and devices that may be used to predict rut performance are some of the topics under review. 2.2 Permanent Deformation Permanent deformation, usually referred to as rutting, is an unrecoverable deformation visible as a depressed channel in the wheelpath of the roadway [3]. It is a progressive movement of materials under static or cyclic loads either in the top (asphalt) layer or the underlying layers [4]. One or a combination of factors ranging from mixture 7

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8 design, selection of materials to inadequate compaction of the pavement or underlying layers, during construction may cause rutting. 2.2.1 Types of Rutting Rutting usually manifests as a depressed channel in the wheelpath on the surface of the pavement. The process through which it occurs can classify the types of rutting. These are densification, shoving, and raveling. 2.2.1.1 Rutting by densification Densification rutting occurs when there is additional compaction in the pavement surface or in any of the underlying layers (base, subbase or subgrade) after the road is open to traffic. The surface may undergo further compaction under traffic loading resulting in rutting when compaction is inadequate during construction of the pavement. Asphalt concrete pavements are usually constructed at initial air void content of 7-8%. It is anticipated that further compaction of the pavement will occur under traffic to around 4% air voids, after which conditions may stabilize. Densification, in general, is not a problem if the asphalt surface is uniformly compacted by traffic. However, with channelized traffic flow, most of the densification occurs in the wheelpath, creating longitudinal ruts. The base or subbase may undergo further compaction resulting in rutting of the pavement surface when there is inadequate compaction of these layers during construction or when the pavement surface is under designed or when there is poor subsurface drainage. The subgrade may also undergo compaction resulting in rutting when there is inadequate pavement structure above it to reduce the subgrade vertical stress/strain to allowable limits.

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9 Weak and yielding layers below the pavement structure may subside from traffic loading resulting in subsidence ruts. These tend to be fairly wide (750-1000 mm) with a shallow sloping saucer shape cross section [1]. This study mainly focused on rutting in the asphalt layer (topmost layer). 2.2.1.2 Rutting by raveling This is a type of rutting caused by the loss of material in the wheelpath. Dislodgement of individual aggregate particles under the action of tires occurs when there is inadequate compaction, low asphalt content or excessive aging of the asphalt binder, which usually result in loss of adhesion between the aggregates and the asphalt binder. Ruts caused by raveling tend to be dry, ragged looking and non-uniform. Rut resulting from the loss of surface material may also be due to abrasion. In this situation aggregate particles wear out if traffic conditions are too abrasive or the aggregates are soft. These ruts are continuous with more resistant aggregates particles exposed and sticking out in the wheelpaths [1]. 2.2.1.3 Rutting by shoving At low air void contents (less than 4%) shear deformation may occur within the asphalt mixture under traffic loading. In this situation pavement material is laterally displaced along shear planes within the mixture, which shows signs of mixture instability. Shoving may be transverse or longitudinal. The rut is usually seen as depression in the loaded area in the wheel path and ridges appear along both edges of the wheelpaths [1]. Shear deformation is usually caused by lack of resistance to shear stresses generated in the pavement surface from tire pressures. This lack of shear resistance of the mixture has been observed by some researchers to be dependent on asphalt type, asphalt content and weak aggregate skeleton. Temperature and rate of loading as well as the magnitude of

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10 loading also influences this type of rutting. Sometimes shear weakness in pavements may be due to moisture damage [1]. 2.2.2 Mixture Properties that Influence Rutting Resistance Hot-mix asphalt is a material composed of aggregates and asphalt binder. Ideally the aggregate skeleton should be capable of supporting and carrying the traffic loads applied to the mixture if it is sufficiently contained and kept bonded together at all times. Since the aggregate particles are not very cohesive the asphalt binder acts as a glue or a bonding material to keep the aggregate skeleton together. However, the asphalt binder must be sufficiently strong to resist excessive shear loads generated between the aggregate particles. If the binder is not strong enough, especially in hot weather, rolling tires can dislodge aggregate particles and shear deformation may easily occur [1]. The selection of the right aggregate structure and the choice of the most appropriate binder having the required properties are therefore very important for HMA to resist rutting. Some of the aggregate properties that influence shear properties and therefore, rut resistance are particle shape, texture and crushed faces and gradation. The viscosity or the stiffness is also a property of the asphalt binder that affects rut resistance; a higher viscosity or stiffer binder, especially at higher temperatures, results in higher rut resistance. Asphalt content, dust to asphalt ratio or percent of mineral filler and film thickness are also some of the properties of the mixture that have been found to affect mixture rutting potential and performance [5]. These are some of the design requirements that the Superpave design method specified to increase mixture performance.

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11 2.3 Superpave Mix Design 2.3.1 Material Specifications The Superpave system, developed by SHRP, is composed of a performance-graded asphalt binder specification, a mixture design specification, and a mixture analysis method. The objective of SHRP was to identify performance-based properties that control the behavior of asphalt binders and asphalt mixtures [6,7]. Currently, the Superpave mix design is based on volumetric properties. Performance-based tests are still under development and may be implemented later and included in the specifications. However, the Superpave volumetric mix design addresses permanent deformation by specifying asphalt binder properties, aggregate properties, and gyratory compactor requirements. The Superpave asphalt binder specification uses performance-based properties to specify the contribution of the asphalt binder to shear resistance [8]. This specification uses the rolling thin film oven test (RTFOT) to simulate asphalt binder aging during construction. It requires a minimum value (2.2 kPa) for G*/sin for the RTFOT aged residue as measured by the dynamic shear rheometer (DSR), which is performance based property for rutting. The higher the G*/sin value the more resistant to permanent deformation the mixture will be [9]. Superpave also specifies required aggregate properties to achieve rut-resistant mixtures [10]. In the case of coarse aggregates a minimum percentage of crushed faces is needed to mobilize some required level of rut resistance and this depends on the traffic and depth within the pavement structure. Fine aggregate on the other hand requires a minimum value of angularity in the fine aggregates angularity test (FAA) to achieve an acceptable rut resistant mixture. The purpose of this aggregate specification is to provide adequate level of inter-particle friction. Aggregate gradation is also found to influence rut

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12 potential of mixtures. The Superpave gradation uses control points and a restricted zone to control the use of sand and encourage the use of larger stone particles in the mixture to develop a coarse skeleton. 2.3.2 Method of Compaction It has been established that the method of compaction used during design influences the properties of mixtures [11]. The Superpave design method uses a gyratory compactor for mixture compaction. The Superpave gyratory compactor is capable of monitoring the rate of densification during compaction and it simulates the field compaction process. There was no reference to measurement for shear resistance of mixtures in the Superpave mixture volumetric design, but some recent studies on these gyratory compactors have shown that in the compaction process strong aggregate skeletons will produce a densification curve with a higher slope. Some new models of the gyratory compactor, for instance the Servopac, have been equipped to measure the shear strength of the mix in the process of compaction. As the mix is compacted, its shear strength increases, and if the mix has adequate shear strength, the shear strength remains constant with the number of gyrations for a period and begins to lose shear after a high number of gyrations. However, if the mix is susceptible to shear failure, then its shear strength decreases soon after a few numbers of gyrations [12]. A relatively unstable mix is expected to lose shear strength rapidly with number of gyrations. Theoretically, a mix that increases or retains shear strength between 5 and 2 percent air voids level can be identified as a well-performing mix, whereas a mix that loses strength between 5 and 2 percent air voids level can be identified as an unstable mix [12]. The Gyratory Testing Machine, also a gyratory compactor, is also capable of measuring the shear strength of the mix during compaction.

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13 2.3.4 Mixture Design The Superpave method requires that the designed mixture, at the design number of gyrations (N des ), have a density of 96 percent of G mm or 4 percent air voids. The mixture cannot achieve a density of above 89 percent of G mm at the initial level of compaction (N ini ). The mixture must also have a minimum value of voids in mineral aggregates (VMA) and a standard range set for voids filled with asphalt (VFA) also at the design number of gyrations. The VMA is dependent on the nominal maximum size of the aggregate and the VFA is dependent on the designed traffic level. 2.3.5 Shortfalls of the Superpave Mix Design As of now the Superpave volumetric mix design has been widely implemented in many States within the U.S. and a lot of successes have already been achieved but researchers have raised major concerns and many issues about some of the design specifications in relation to satisfactory mixture performance. It has been observed that the “Restricted Zone,” used to control the amount of sand particles in the aggregate gradation and, therefore, prevent tender mixes, is not very effective as a tool for screening good and poor aggregate structure. There are some aggregate gradations that pass through the restricted zone but still meet the other requirements and are found to perform well in sharp contrast to what is expected [13,14]. This means that the continued use of this criterion causes a situation to arise whereby potentially good mixes are rejected outright. Another observation is that some HMA mixtures satisfying all Superpave volumetric criteria, including VMA, may have aggregate gradations with a poor structure [5]. These mixtures may tend to have poor rut resistance. In the past few years several studies have been conducted with regard to the VMA criterion and it has been shown that

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14 the VMA criterion based solely on nominal maximum aggregate size may lead to rut susceptible mixtures, with greater effect on coarse graded mixtures [15,16]. This is because there are cases whereby the asphalt content may have to be increased excessively or the aggregate may have to be gap-graded purposely for the mixture to pass the VMA criterion. Karakouzian et al. have shown that continuous graded mixtures result in 50 percent higher rut-resistant mixtures than gap-graded mixtures [17]. It has been realized that the VMA is not only dependent on nominal maximum aggregate size but also may depend on such factors as the texture of the coarse aggregates and dust in fine aggregates [18]. Some have proposed making VMA dependent on certain gradation parameters such as percent passing the 2.36 mm sieve [5,16]. Hishop and Coree have shown that many good mixtures are subject to rejection based solely on failing to meet the VMA criterion, and proposed setting up a volumetric design based on aggregate gradation, shape and texture [19]. Hishop and Coree also suggested the use of fineness modulus and percent crushed fine and coarse aggregates [20]. Some studies have also shown that in addition to controls on weight retained on critical sieve sizes, the shape of the gradation curve should be controlled [21,22]. All these studies have given a strong indication that even though there exist some level of controls for the selection of suitable aggregate gradations, the current controls may not be enough to prevent gap-graded mixtures with a poor aggregate structure [also 23,24]. There is, therefore, the need to evaluate the gradation parameters to ensure a continuous gradation and provide tighter gradation guidelines.

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15 2.4 Mixture Performance Testing Performance testing may be in the form of a performance-based test, a performance related test, or an empirical test. A performance-based test measures an engineering property that directly relates to performance. This measured property can be used in a mechanistic model to predict response to load. A performance related test measures an engineering property that is connected to performance but is not directly used to predict performance. Rather it is used in an empirical model to predict performance. Such properties may not be used to predict material response directly but they can be used knowing that there is a fundamental relationship between the property measured and performance on the road. Performance related properties include mixture stiffness, dynamic creep, repeated shear, and static creep [1]. Creep test was developed to estimate the rutting potential of asphalt mixtures. This test is conducted by applying a static load to a HMA specimen and the resulting permanent deformation with time, which closely relates to field performance, is measured [25]. The loading system may be a “uniaxial static confined or unconfined” loading. An important part of the creep test that is often utilized is the rebound portion of the creep curve obtained after the load is removed. The permanent deformation, used as a measure of rutting performance, is the maximum deformation minus the amount of rebound. Performance may also be measured in terms of the creep compliance-a ratio of the strain to the applied load at the required test temperature and time of loading. Empirical tests do not measure a fundamental engineering property but just measures the response to an applied load. The response can be linked to rutting performance. Sometimes empirical tests are designed as a miniature simulation of the

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16 road. The test result is a response to an applied loading that depends on the specimen geometry, geometry of the applied load and scale effects. The Superpave volumetric mix design has not yet proven to be a tool for characterizing mixture performance. At the time of introduction and subsequent adoption of the Superpave mix design, the Superpave performance-based mixture tests, which form the second and third level of the SHRP, were not finalized [25]. Apart from the creep test (mentioned above), various tests have been proposed and used to measure resistant to permanent deformation with varying successes. There seems to be a lot of work yet to be done in this area. Some of the tests that have been previously used to evaluate the rut potential of HMA mixtures include some type of laboratory wheel tracking testing devices [25]. Several types of this wheel tracking test device (also known as rut testers), which are sort of empirical in concept, have been manufactured. Some of these devices conduct tests underwater and some in a temperature-controlled chamber, thus testing can be performed under dry or wet conditions. The Georgia load wheel tester, a type of wheel tracking test device, has been used by the FDOT to test three pavements and it was observed that there was agreement between the field rutting and rutting in the Georgia load wheel tester [1]. Therefore, they do seem to provide some laboratory measure of potential for rutting. Other types of rut testers that have been used in the past to measure rut resistance are the LCPC rut tester and the Hamburg rut tester [26]. Testing equipment used in this study to measure parameters for estimating rut resistance or rut potential of HMA mixtures are (1) the Servopac Gyratory Compactor, (2) the Asphalt Pavement Analyzer and (3) the Gyratory Testing Machine.

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17 2.4.1 Servopac Gyratory Compactor One of the most important outcomes of the SHRP effort was the introduction of the Superpave Gyratory Compactor (SGC). This compactor is able to compact HMA samples to a density similar to that obtained in the field under traffic. It also tends to orient the aggregate particles similar to that observed in the field [25]. For this compactor, Superpave specifies the rate of gyration, the compaction pressure, and the angle of gyration. There is the need to use the SGC as a tool for predicting in-place performance of mixes; that is a procedure to identify inferior mixes in the laboratory during production [12]. Several potential techniques such as compaction energy [27] have been introduced that use the SGC data to identify the in-place mix performance; there is the need to find out whether the measured parameters can be used to identify unstable mixes at production. The Servopac Gyratory compactor, a model of the Superpave Gyratory Compactor developed in Australia, was used as the gyratory compactor in this study. It is a servo-controlled gyratory machine, designed to apply a static compressive force to an asphalt specimen and simultaneously apply a gyratory motion to the sample. The Servopac is designed to measure the change in height and the shear resistance of the sample during compaction and is capable of compacting at a fixed angle of up to 3 degrees. The gyratory shear and the gyratory ratio (ratio of the number of compaction required to achieve 98% density to that required to achieve 95% density) are some of the parameters that can be computed from measurements obtained from the Servopac. These have been used as indices to estimate rut resistance of HMA mixes [12,28,29]. Some researchers have observed a relationship between the gyratory shear strength parameter measured in the gyratory compactors and resistance to rutting [30-33]. Work performed

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18 by Butcher [33] tends to show that the gyratory shear parameter measured from the Servopac may potentially predict rutting performance of asphalt mixtures. 2.4.2 Asphalt Pavement Analyzer The Asphalt Pavement Analyzer (APA) is a variation of the Georgia loaded wheel tester. It is capable of measuring the rut depth of HMA specimen loaded under a wheel roller and a pressurized hose in the laboratory. Test specimens are first compacted in a gyratory compactor to a predetermined air void before being subjected to the APA testing. The test is generally conducted for 8000 cycles with a wheel load of 445 N (100 lb) and a hose pressure of 690 kPa (100 psi), which simulates tire pressure and field loading conditions; specimens are confined in a mold to. It is performed at an average temperature for a specific region; testing can be done in a temperature controlled air chamber or water bath (if moisture damage effect on rutting is to be assessed). The APA has been used for performing rutting tests [34] and the results correlated highly with actual in-place rut depths, even though discrepancies were observed because of differences in pavement ages and applied number of ESAL’s to the pavement at the time of evaluation. It was observed also from these tests that the APA results were sensitive to aggregate gradation based on a statistical differences in rut depths measured. Thus, the APA has the potential to predict rut resistance and identify inferior mixes of HMA mixtures; it is a potential tool for performance testing of asphalt mixtures.

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19 2.4.3 Gyratory Testing Machine The Gyratory Testing Machine (GTM) is a gyratory compactor developed by the U.S Army Corps of Engineers. It can be used for the design and evaluation of HMA mixture quality. This machine was designed to compact HMA mixtures with a kneading process that simulates the action of rollers during construction and has the ability to vary the vertical pressure, the angle of gyration, and the number of gyrations to simulate field compaction equipment and traffic loading conditions [25]. Two parameters, the gyratory stability index (GSI) and the gyratory shear strength (G s ), are determined from the GTM during compaction. The GSI is determined from the ratio of the final gyratory angle to the initial angle, and it is used as an index to identify unstable mixes. A GSI value of 1.0 is an indication of a stable mix but a value significantly above 1.1 usually indicates unstable mixtures. The strength of a mix can be considered as its resistance to compaction. For instance, a mix that needs more compactive effort in the laboratory or more traffic applications in the field to densify from say, 5% to 2% air voids has more strength than a mix that requires less compaction or less traffic applications. The G s, which is measured at high temperatures during compaction, is a primary measure of aggregate properties. It is these aggregate properties that must provide the support to resist permanent deformation caused by traffic [25]. Sigurjonsson and Ruth used the GTM to assess the effects of aggregate characteristics and changes in binder content for HMA mixtures during compaction. They observed that mixtures with different types of aggregate but similar gradation might give entirely different gyratory shear response [32]. Mallick also used the G s , GSI and the gyratory ratio, obtained from the GTM, to differentiate between good and poor mixes and this correlated well with in-place rut depth measurements obtained in the field [12].

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20 CHAPTER 3 MATERIALS AND TESTING METHODS 3.1 Introduction Six (6) FDOT Superpave mixtures that have already been placed in the State of Florida, (see Table 3-1), and whose field performances have been measured and evaluated (except one), for at least two years, were adopted for this study. All the FDOT original mixtures selected had a Reclaimed Asphalt Pavement (RAP) component of 15%35% that formed part of the aggregate c onstituent in the mix, the Job Mix Formula (JMF). However, the RAP material was no longe r available at the time of this research, and so it was eliminated and the percentages of the other aggregates adjusted to maintain the same or very close gradation for each mix. This exercise was not expected to change the outcome of the study very much since the main objective of the research is to compare the effects of aggregate grada tions and other mix properties on rutting resistance. Table 3-1: Selected Pavements and Locations Project No. (FDOT) Project No. (UF) Route County 2134391 1 I-10 Madison 2139971 2 I-75 Hamilton 2139961 3 I-75 Hamilton 2423161 5 I-95 Brevard 2325941 7 Turnpike Palm Beach 222596 8 I-10 Leon County

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21 The Superpave Volumetric Mix Design procedure was used to design and produce the mixtures for five of the aggregate blends using the design job mix formulas (projects #1, #2, #3, #5, and #7) obtained without the RAP. The sixth mixture (project #8) was obtained by sampling the mix from the mixing plant of the contractor for that project, because construction with that particular mix was still in progress just before this study. Mixtures were then prepared in accordance with these designs and they were tested in the Servopac Gyratory Compactor, the Asphalt Pavement Analyzer (APA) and in the Gyratory Testing Machine (GTM) to determine their resistance to rutting. Three replicates were tested for each mixture in the Servopac and in the GTM but two samples were tested for each project in the APA. 3.2 Materials 3.2.1 Aggregates The original aggregates, used by the FDOT for the monitoring projects, and their sources, are shown in Table 3-2. Also shown in the same table are the percentages of each aggregate used in the JMF. Project #1 and #5 are 9.5mm nominal maximum size coarse graded mixtures, project #2, #3and #8 are 12.5mm nominal maximum size coarse graded mixtures and project #7 is a 12.5mm nominal maximum size fine graded mixture. Gradations for these aggregates and the JMF are given in Table 3-2. The JMF for the FDOT mixes are plotted on 0.45 power charts, which are shown in figures in Appendix A. Aggregates in table 3-2 were obtained from the same sources and blended without the RAP (Milled material), because they were not available at the time of this research. These new blends have very close gradations to the original JMF; as close as can possibly

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22 be achieved. In the case of project #2, a fine portion of the W-10 Screenings had to be introduced (referred to as W-10 Screenings 2) to replace the RAP volumetrically in order to get a closer gradation to the original. This is because the RAP mostly contributed the fine part of this JMF. The new blends are shown in Table 3-3 and their plots on the 0.45 power chart are compared to the originals in figures in Appendix A. 3.2.2 Asphalt Binder The asphalt binder used for the study is an AC-30 binder with a PG-67-22 grading. This was obtained from Coastal Petroleum Company in Jacksonville and is a commonly used binder in the state of Florida. 3.3 Mixture Design The Superpave Volumetric Mix Design procedure was used to design the HMA samples used for the testing and evaluation in this research. The design procedure is based on the selection of asphalt content (% AC content) for the aggregate blends using the volumetric properties of the mix as the primary criteria. These include a 4% air voids and a set of minimum values for the voids in mineral aggregates (VMA) and a range of values for voids filled with asphalt (VFA) as specified by Superpave for a given nominal maximum size aggregate and expected traffic level respectively. 3.3.1 Aggregate Preparation and Batching The following procedure was used for the preparation of the aggregates: Virgin aggregates were oven-dried for at least 12 hours at a temperature of 235 F after which they are allowed to cool down at room temperature. The aggregates were then sieved and separated into their individual particle sizes (3/4”, ”, 3/8”, #4, #8, #16, #30, #50, #100, #200, -200).

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23 Four samples of 4500g and 1500g were batched from the aggregates, in accordance with the Job Mix Formula (JMF), for mix used for compaction in the Pine Gyratory Compactor and for the determination of theoretical maximum density (Rice density) respectively. Tables showing batch weights for the aggregates are given in Appendix A. 3.3.2 Mixing The aggregates and the asphalt are heated in the oven at a temperature of 300F for about 3 hours. The mixing bucket and the spatulas are also heated to this temperature. After 3 hours the aggregates and the asphalt are removed from the oven and mixed in the bucket for about 5 minutes or until the aggregates are well coated with the asphalt. The amount of asphalt used for each of the three samples relates to the estimated optimum asphalt content, P b by P b -0.5, P b and P b +0.5. Three 4500g batched aggregates are mixed and compacted in the first place in the Pine Gyratory Compactor and three 1500g batched aggregates are mixed for the determination of rice density (G mm ) in accordance with AASHTO T 209-94 or ASTM D2041. 3.3.4 Short Term Oven Aging (STOA) Before the samples are compacted or tested on rice density, they are spread on a pan and heated in an oven for about 2 hours at a temperature of 275F to induce a short term oven aging (STOA). While in the oven the mix is stirred after one hour to obtain a uniformly aged sample.

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24 Table 3-2: Aggregate Sources for Selected FDOT Mixtures Proj. Mix Type of FDOT Pit No. Producer % in No. No. Material Code JMF 1 970051A Milled material 20 #89 Stone 51 GA 185 Martin Marietta 45 W-10 Screenings 20 GA 185 Martin Marietta 25 M-10 Screenings 21 GA 185 Martin Marietta 10 2 970062A Milled material 35 #7 Stone 52 GA 185 Martin Marietta 20 #89 Stone 51 GA 185 Martin Marietta 38 W-10 Screenings 20 GA 185 Martin Marietta 7 3 970037A Milled material 15 S1A Stone 41 38-036 Limerock industries 15 S1B Stone 56 87-145 Tarmac Florida 35 200 Screenings 20 29-023 Limerock industries 35 5 980126B Milled material 15 FC-3 Stone 55 87-090 Rinker material 55 Medium asphalt Scr 21 87-090 Rinker material 5 W-10 Screenings 20 GA-178 Southern aggregates 25 7 980139A Milled material Ranger const. Ind. 20 S1A Stone 41 87-339 White rock quarries 20 S1B Stone 51 87-339 White rock quarries 10 Asphalt Screenings 20 87-339 White rock quarries 50 8 000805A Milled material 10 S1A Stone 41 38-036 Limerock industries 15 S1B Stone 51 38-228 Martin Marietta 50 New mill screenings 25 38-036 Limerock industries 10 Sand Crowder Crowder Sand Co. 15

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25 Table 3-3: Aggregate Sources and Modify Blends for Research Mixtures Proj. Mix No. Type of FDOT Pit No. Producer % in No. Material Code JMF 1 970051A #89 Stone 51 GA 185 Martin Marietta 50 W-10 Screenings 20 GA 185 Martin Marietta 18.5 M-10 Screenings 21 GA 185 Martin Marietta 31.3 2 970062A #7 Stone 52 GA 185 Martin Marietta 20.2 #89 Stone 51 GA 185 Martin Marietta 47.9 W-10 Screenings 20 GA 185 Martin Marietta 21.2 W-10 Screenings 2 10.7 3 970037A S1A Stone 41 38-036 Limerock 19.2 S1B Stone 56 87-145 Tarmac Florida 33.5 200 Screenings 20 29-023 Limerock 47.3 5 980126B FC-3 Stone 55 87-090 Rinker material 62.8 Medium asphalt Scr 21 87-090 Rinker material 20.8 W-10 Screenings 20 GA-178 Southern 16.4 7 980139A S1A Stone 41 87-339 White rock 24.5 S1B Stone 51 87-339 White rock 12.5 Asphalt Screenings 20 87-339 White rock 63.0 8 000805A Milled material 10 S1A Stone 41 38-036 Limerock 15 S1B Stone 51 38-228 Martin Marietta 50 New mill screenings 25 38-036 Limerock 10 Sand Crowder Crowder Sand 15

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26 020406080100Sieve Size (mm)Percent Passing Project #5 Project #10.0750.1500.3000.6001.182.364.759.512.519.0 Figure 3-1: 9.5 mm-Nominal Maximum Size Gradations (Projects 1 & 5)

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020406080100Sieve Size (mm)Percent Passing Project #2 Project #3 Project #7 Project #80.0750.1500.3000.6001.182.364.759.512.519.025.0 3 7 8 27 2 Figure 3-1: 12.5 mm-Nominal Maximum Size Gradations

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28 3.3.5 Compaction After the STOA, the 4500g samples are compacted in the Pine Gyratory Compactor to N max of 152 gyrations, corresponding to traffic level 5, for all the projects (1,2,3,5,and 8) except for project 7, which was compacted to 134 gyrations, corresponding to traffic level 4. Compacted specimens were allowed to cool for a minimum of 24 hours at room temperature. The Bulk Specific Gravity (G mb ) was then determined in accordance with ASTM D1189 and D2726 for each of the compacted specimen. From the G mm and the G mb the % air voids for each of the 3 specimens are computed at N max . A back-calculation formula was used to determine the % of air voids at N des for each of the specimen at their respective asphalt contents. These values are now used to estimate the asphalt content corresponding to 4% air voids at N des . The fourth aggregate samples of 4500g is now mixed and compacted and the 1500g mixed and tested on rice density using the asphalt content estimated above. This time round the compaction is done for gyrations corresponding to N des , which are 96 gyrations for samples for project 1,2,3,5and 8 but 86 gyrations for project 7. The Superpave Volumetric Properties (VMA, VFA etc) are computed and checked if the fourth specimen meets the criteria for 4% air voids at N des , for the estimated asphalt content. The design is repeated if the Superpave criteria are not met and new asphalt content is selected for evaluation.

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29 Once the optimum asphalt content is determined for each mixture, samples are produced at these asphalt contents for testing in the Servopac Gyratory Compactor, Asphalt Pavement Analyzer and in the Gyratory Testing Machine. Figure 3-3: Pine Gyratory Compactor 3.4 Servopac Gyratory Compactor The Servopac Gyratory Compactor is a compaction device used in the superpave mix design. It has the ability to compact HMA samples to a density similar to that obtained for in-place mixtures in the field under traffic conditions. The three main parameters that control the compaction effort of this equipment for the superpave design

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30 procedure are the vertical pressure, which is set for 600-kPa (87-psi), the angle of gyration set at 1.25, and the number of gyrations, which may be varied to simulate the expected traffic level. [25]. The angle of gyration may also be set at 2.5. The equipment may be used to distinguish between inferior mixtures and good performing mixtures in terms of the extent of compaction attained at a certain number of gyrations and also in terms of the gyratory shear, which is a shear strength parameter measured during compaction. Three (3) samples for each project were compacted at 1.25 and 2.5 in the Servopac Gyratory Compactor to compare their shear properties. The procedure for sample preparation and testing in the Servopac is as follows: 4500g samples of the aggregates are batched in accordance to the required job mix formula. The aggregate and asphalt binder are preheated separately to 300F for about three hours after which they are mixed until the aggregates are thoroughly coated with the binder; amount of binder used is pre-determined to produce Hot Mix Asphalt (HMA) using Superpave Volumetric Mix Design procedures. The mixture is then subjected to two hours of short-term oven aging (STOA) at 275F in accordance to AASHTO PP2. The sample is then removed from the oven and compacted in the 150 mm mold to 200 gyrations in the Servopac. Three samples are compacted at 1.25 and three also at 2.5 for each project. In the process of compaction, the height of the specimen, and the gyratory shear are measured at each gyration.

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31 Each specimen was allowed to cool at room temperature (approximately 25C) for a minimum of 24 hours. After this the Bulk Specific Gravity of the specimen is determined in accordance with AASHTO T 166 or ASTM D 2726. Also the maximum specific gravity of the mixture was determined in accordance with ASTM D 2041 (AASHTO T 209) in a separate test. Now from the height of the specimen the density is determined for each level of gyration. Volumetric properties such as air voids, VMA, VFA and %G mm are also determined for all gyrations. The specimen was allowed to cool at room temperature (approximately 25C) for a minimum of 24 hours. After this the Bulk Specific Gravity of the specimen is determined in accordance with AASHTO T166 or ASTM D 2726. Also the maximum specific gravity of the mixture was determined in accordance with ASTM D 2041 (AASHTO T 209). 3.5 Asphalt Pavement Analyzer Testing Procedure Asphalt Pavement Analyzer (APA) is equipment designed to test the rutting susceptibility or rutting resistance of hot mix asphalt. With this equipment, rut performance test is done by means of a constant load applied repeatedly through pressurized hoses to a compacted test specimen. The test specimen may either be 75mm x 125mm x 300mm beam or 150mm diameter by 75mm thick cylindrical specimen. Cylindrical specimens were used in this study. The procedure for sample preparation and testing is as follows: 4500g samples of the aggregates are batched in accordance to the required job mix formula. The aggregate and asphalt binder are preheated separately to 300F for about three hours after which they are mixed until the aggregates are thoroughly coated

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32 Figure 3-4: Servopac Gyratory Compactor with the binder; amount of binder used is pre-determined to produce an optimum Hot Mix Asphalt (HMA) using Superpave Volumetric Mix Design procedures. The mixture is then subjected to two hours of short-term oven aging at 275F in accordance to AASHTO PP2. The sample is compacted, at the above temperature, to contain 7.0% air voids in the Pine Gyratory Compactor. This is done by first determining the compaction height needed to obtain the required air void content from the compaction results obtained for the mixture design. The mix is then compacted to the determined height.

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33 The specimen was allowed to cool at room temperature (approximately 25C) for a minimum of 24 hours. After this the Bulk Specific Gravity of the specimen is determined in accordance with AASHTO T 166 or ASTM D 2726. The maximum specific gravity of the mixture was determined in accordance with ASTM D 2041 (AASHTO T 209). Then the air void content of the specimen was determined in accordance with ASTM D 3203 (AASHTO T269) to check if the needed air void content is achieved. The specimen is trimmed to a height of 75mm and allowed to air dry for about 48 hours. The specimen was preheated in the APA test chamber to a temperature of 60C (140F) for a minimum of 6 hours but not more than 24 hours before the test is run. The hose pressure gage reading was set to 100psi. The load cylindrical pressure reading for each wheel was set to obtain a load of 100lbs. Secure the preheated, molded specimen in the APA, close the chamber doors and allow 10 minutes for the temperature to stabilize prior to starting the test. 25 wheel strokes were applied to seat the specimen before initial measurements was taken. After the 25 cycles, the elevations at four locations on the specimens were manually measured. The mold and the specimen are securely positioned in the APA, close the chamber doors and allow 10 minutes for the temperature to stabilize. Restart the APA and continue rut testing, now for 8000 cycles.

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34 After the 8000 cycles are completed, the rut depths at each of the four locations on the specimen are manually measured. The APA is equipped with automatic rut depth measuring systems that take the readings during the test, but this may vary from the manually taken measurements. The difference between the initial and final rut depth readings are calculated for each location and averaged. The average rut depth is reported for the particular mixture. 3.6 Gyratory Testing Machine Procedure The Gyratory Testing Machine (GTM) was developed by the corps of Engineers and is an effective tool for evaluating Hot Mix Asphalt mixture quality. Apart from determining the allowable asphalt/bitumen content, the GTM is also capable of measuring the shear strength of the mixture during compaction. It has the advantage of being able to vary the vertical pressure and gyratory angle to simulate field compaction and traffic. The procedure for sample preparation and testing is as follows: 1100g samples of the aggregates are batched in accordance to the required job mix formula. The aggregate and asphalt binder are preheated separately to 300F for about three hours after which they are mixed until the aggregates are thoroughly coated with the binder; amount of binder used is pre-determined to produce an optimum HMA using Superpave Volumetric Mix Design procedures. The mixture is then subjected to two hours of short-term oven aging at 275F (135C) in accordance to AASHTO PP2.

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35 Figure 3-5: Asphalt Pavement Analyzer (APA) Size of specimen – The GTM is designed for test molds of diameters 101.6mm (4-in.), 152.4mm (6-in.), and 203.2mm (8-in.). The GTM model used for this project uses mold size of 101.6mm (4-in.). The short-term oven aged sample is transferred right away from the oven into the mold. The mold is quickly fixed in the GTM mold chuck. The lower ram is raised to hold the mold, by turning the vertical pressure control up, as the front piece of the mold

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36 chuck is installed and securely tightened. It must be ensured that the upper disk is fixed into the mold as the mold is raised. The heater is turned on. The vertical pressure is adjusted to 120psi (828kPa), which is approximately equal to truck tire inflation pressure. Set the roller pressure to an initial reading of 9psi. The gyratory angle is set to 2. The dial gauge reading is adjusted to zero. The gyrograph pen is positioned correctly on the paper and the switch turned on. The counter is now adjusted to read zero. The roller is now turned on to start compaction. At intervals of 50 revolutions the roller is stopped and the roller pressure reading is recorded. The dial gauge reading is also taken at all four positions of the roller at 0, 90, 180, and 270 and the average computed and recorded as the specimen height at this stage. The gyrograph pen may be switched off during this time and turned back on when the roller is about to start again. Calculate the change in density of the specimen at interval of 50 revolutions. The roller is turned on again and the process is continued for every 50 revolutions until equilibrium of the compaction of the specimen is reached. The equilibrium of the compaction process is reached when the change in density of the specimen is equal to or less than 8 kg/m 3 (0.5 lb./ft 3 ) per 50 revolutions. The specimen is extruded from the mold and allowed to cool at room temperature (approximately 25C) for a minimum of 24 hours. After this the Bulk Specific

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37 Gravity of the specimen is determined in accordance with AASHTO T 166 or ASTM D 2726. Also the maximum specific gravity of the mixture is determined in accordance with ASTM D 2041 (AASHTO T 209) in a separate test on a different sample of the mixture. Figure 3-6: Gyratory Testing Machine (GTM)

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CHAPTER 4 SUMMARY AND ANALYSES OF TEST RESULTS 4.1 Introduction Job Mix Formulas for Superpave Mixtures (identified in this study as mixtures #1, #2, #3, #5, #7, and #8) with known field rutting performance, except #8, were reproduced in the laboratory and tested in the Servopac Gyratory Compactor, the Asphalt Pavement Analyzer and the Gyratory Testing Machine to determine if their laboratory rutting (shear) resistances and mixture properties correlate with their field rutting. The study also aimed at investigating whether gradation for some of these mixtures was a factor in their relatively poor field rutting performance. Attempt is also made to verify if any of the equipment mentioned above (Servopac, APA, GTM) has the potential to identify Superpave mixture rutting performance in the laboratory. The Superpave mixture design protocol was varied for two of the mixtures (#1 and #5) to identify the effects on the rutting resistance by failing the Superpave VMA requirements, but maintaining approximately 4% air void. This was achieved by producing and testing samples of these two mixtures at approximately 4% air voids but below the VMA requirement. The effect of gradation was investigated by modifying the blend for mixture #1 (referred to in this study as mixture #M1). In mixture #M1, 8% of aggregate on the , sieve instead of 1%, was retained to increase the coarse material in the mix and thus changing the gradation or aggregate structure. #M1 was also tested and its rutting resistance parameters evaluated and compared to that of #1 as in section 4.7. 38

PAGE 51

39 The mixture design data and volumetric properties of the mixtures are given in Appendix B. A summary of field rutting data and the laboratory test results are given and fully discussed. Most of the testing data are also shown in Appendix C. 4.2 Field Rutting The field rut depths were measured using a transverse profiler at thirty locations of each project. Average accumulated rut depths at the end of two years after construction and opening of the pavements to traffic are shown in Table 4-1. The measured rut depths show that mixtures #1 and #2 experienced higher rutting while mixtures #3, #5 and #7 show relatively lower rutting within the same period This is also shown in Figure 4-1 which compares the field rut depth per ESALs between projects. Thus the indications are that mixtures #3, #5 and #7 performed better in the field in terms of rutting resistance than mixtures #1 and #2. Rut data for mixture #8 had not yet been obtained at the time of this report. Therefore, mixture #8 may be left out of the discussion at the moment, where appropriate, and referenced when necessary or when field data are available. Table 4-1: Field Rutting Data Project No. Avg. Field Rut Depth After Year 2 (mm) Estimated ESALs at Year 2 1 5.1 1.48 x 10 6 2 5.6 2.31 x 10 6 3 3.8 2.54 x 10 6 5 2.9 2.10 x 10 6 7 2.5 2.99 x 10 6

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40 \000\000\000\000\000\000\000 )TjETEMC/P <>BDCQ 1 1 1 scnBT/T3_4 1 Tf1.92 0 0 -11.52 153.6 668.1599 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q153.48 675.18 24.72 -214.74 reW* nBT/T3_4 1 Tf1.92 0 0 -11.52 151.68 656.6399 Tm()TjETEMC/P <>BDCQ BT/T3_4 1 Tf1.92 0 0 -11.52 153.5999 656.6399 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q153.48 675.18 24.72 -214.74 reW* nBT/T3_4 1 Tf1.92 0 0 -11.52 151.6799 645.1199 Tm()TjETEMC/P <>BDCQ BT/T3_4 1 Tf1.92 0 0 -11.52 153.5999 645.1199 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q153.48 675.18 24.72 -214.74 reW* nBT/T3_4 1 Tf1.92 0 0 -11.52 151.6799 633.5999 Tm()TjETEMC/P <>BDCQ BT/T3_4 1 Tf1.92 0 0 -11.52 153.5999 633.5999 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q153.48 675.18 24.72 -214.74 reW* nBT/T3_4 1 Tf1.92 0 0 -11.52 151.6799 622.0799 Tm()TjETEMC/P <>BDCQ BT/T3_4 1 Tf1.92 0 0 -11.52 153.5999 622.08 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q153.48 675.18 24.72 -214.74 reW* nBT/T3_4 1 Tf1.92 0 0 -11.52 151.6799 610.56 Tm()TjETEMC/P <>BDCQ BT/T3_4 1 Tf1.92 0 0 -11.52 153.5999 610.5599 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q153.48 675.18 24.72 -214.74 reW* nBT/T3_4 1 Tf1.92 0 0 -11.52 151.6799 599.0399 Tm()TjETEMC/P <>BDCQ BT/T3_4 1 Tf1.92 0 0 -11.52 153.5999 599.0399 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q153.48 675.18 24.72 -214.74 reW* nBT/T3_4 1 Tf1.92 0 0 -11.52 151.6799 587.5199 Tm()TjETEMC/P <>BDCQ BT/T3_4 1 Tf1.92 0 0 -11.52 153.5999 587.5199 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q153.48 675.18 24.72 -214.74 reW* nBT/T3_4 1 Tf1.92 0 0 -11.52 151.6799 575.9999 Tm()TjETEMC/P <>BDCQ BT/T3_4 1 Tf1.92 0 0 -11.52 153.5999 575.9999 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q153.48 675.18 24.72 -214.74 reW* nBT/T3_4 1 Tf1.92 0 0 -11.52 151.6799 564.4799 Tm()TjETEMC/P <>BDCQ BT/T3_4 1 Tf1.92 0 0 -11.52 153.5998 564.4799 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q153.48 675.18 24.72 -214.74 reW* nBT/T3_4 1 Tf1.92 0 0 -11.52 151.6798 552.9599 Tm()TjETEMC/P <>BDCQ BT/T3_4 1 Tf1.92 0 0 -11.52 153.5998 552.9599 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q153.48 675.18 24.72 -214.74 reW* nBT/T3_4 1 Tf1.92 0 0 -11.52 151.6798 541.4399 Tm()TjETEMC/P <>BDCQ BT/T3_4 1 Tf1.92 0 0 -11.52 153.5998 541.4399 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q153.48 675.18 24.72 -214.74 reW* nBT/T3_4 1 Tf1.92 0 0 -11.52 151.6798 529.9199 Tm()TjETEMC/P <>BDCQ BT/T3_4 1 Tf1.92 0 0 -11.52 153.5998 529.9199 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q153.48 675.18 24.72 -214.74 reW* nBT/T3_4 1 Tf1.92 0 0 -11.52 151.6798 518.3999 Tm()TjETEMC/P <>BDCQ BT/T3_4 1 Tf1.92 0 0 -11.52 153.5998 518.3999 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q153.48 675.18 24.72 -214.74 reW* nBT/T3_4 1 Tf1.92 0 0 -11.52 151.6798 506.8799 Tm()TjETEMC/P <>BDCQ BT/T3_4 1 Tf1.92 0 0 -11.52 153.5998 506.8799 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q153.48 675.18 24.72 -214.74 reW* nBT/T3_4 1 Tf1.92 0 0 -11.52 151.6798 495.3599 Tm()TjETEMC/P <>BDCQ BT/T3_4 1 Tf1.92 0 0 -11.52 153.5997 495.3599 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q153.48 675.18 24.72 -214.74 reW* nBT/T3_4 1 Tf1.92 0 0 -11.52 151.6797 483.8399 Tm()TjETEMC/P <>BDCQ BT/T3_4 1 Tf1.92 0 0 -11.52 153.5997 483.8399 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q153.48 675.18 24.72 -214.74 reW* nBT/T3_4 1 Tf1.92 0 0 -11.52 151.6797 472.3199 Tm()TjETEMC/P <>BDCQ BT/T3_4 1 Tf1.92 0 0 -11.52 153.5997 472.3199 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q153.48 675.18 24.72 -214.74 reW* nBT/T3_4 1 Tf1.92 0 0 -11.52 151.6797 460.7999 Tm(\000\000\000\000\000\000\000 \000\000\000\000\000\000)TjETEMC/P <>BDCQ q215.16 611.16 24.72 -150.72 reW* n1 1 1 scnBT/T3_5 1 Tf1.92 0 0 -11.52 215.04 610.56 Tm()TjETEMC/P <>BDCQ 1 1 1 scnBT/T3_5 1 Tf1.92 0 0 -11.52 216.96 610.5599 Tm(\000\000\000)TjETEMC/P <>BDCq215.16 611.16 24.72 -150.72 reW* nBT/T3_5 1 Tf1.92 0 0 -11.52 230.4 610.5599 Tm(\000\000)TjETEMC/P <>BDCQ q215.16 611.16 24.72 -150.72 reW* nBT/T3_5 1 Tf1.92 0 0 -11.52 215.04 599.0399 Tm()TjETEMC/P <>BDCQ BT/T3_5 1 Tf1.92 0 0 -11.52 216.96 599.0399 Tm(\000\000\000)TjETEMC/P <>BDCq215.16 611.16 24.72 -150.72 reW* nBT/T3_5 1 Tf1.92 0 0 -11.52 230.4 599.0399 Tm(\000\000)TjETEMC/P <>BDCQ q215.16 611.16 24.72 -150.72 reW* nBT/T3_5 1 Tf1.92 0 0 -11.52 215.04 587.5199 Tm()TjETEMC/P <>BDCQ BT/T3_5 1 Tf1.92 0 0 -11.52 216.9599 587.5199 Tm(\000\000\000)TjETEMC/P <>BDCq215.16 611.16 24.72 -150.72 reW* nBT/T3_5 1 Tf1.92 0 0 -11.52 230.3999 587.5199 Tm(\000\000)TjETEMC/P <>BDCQ q215.16 611.16 24.72 -150.72 reW* nBT/T3_5 1 Tf1.92 0 0 -11.52 215.0399 575.9999 Tm()TjETEMC/P <>BDCQ BT/T3_5 1 Tf1.92 0 0 -11.52 216.9599 575.9999 Tm(\000\000\000)TjETEMC/P <>BDCq215.16 611.16 24.72 -150.72 reW* nBT/T3_5 1 Tf1.92 0 0 -11.52 230.3999 575.9999 Tm(\000\000)TjETEMC/P <>BDCQ q215.16 611.16 24.72 -150.72 reW* nBT/T3_5 1 Tf1.92 0 0 -11.52 215.0399 564.4799 Tm()TjETEMC/P <>BDCQ BT/T3_5 1 Tf1.92 0 0 -11.52 216.9599 564.4799 Tm(\000\000\000)TjETEMC/P <>BDCq215.16 611.16 24.72 -150.72 reW* nBT/T3_5 1 Tf1.92 0 0 -11.52 230.3999 564.4799 Tm(\000\000)TjETEMC/P <>BDCQ q215.16 611.16 24.72 -150.72 reW* nBT/T3_5 1 Tf1.92 0 0 -11.52 215.0399 552.9599 Tm()TjETEMC/P <>BDCQ BT/T3_5 1 Tf1.92 0 0 -11.52 216.9599 552.9599 Tm(\000\000\000)TjETEMC/P <>BDCq215.16 611.16 24.72 -150.72 reW* nBT/T3_5 1 Tf1.92 0 0 -11.52 230.3999 552.9599 Tm(\000\000)TjETEMC/P <>BDCQ q215.16 611.16 24.72 -150.72 reW* nBT/T3_5 1 Tf1.92 0 0 -11.52 215.0399 541.4399 Tm()TjETEMC/P <>BDCQ BT/T3_5 1 Tf1.92 0 0 -11.52 216.9599 541.4399 Tm(\000\000\000)TjETEMC/P <>BDCq215.16 611.16 24.72 -150.72 reW* nBT/T3_5 1 Tf1.92 0 0 -11.52 230.3999 541.4399 Tm(\000\000)TjETEMC/P <>BDCQ q215.16 611.16 24.72 -150.72 reW* nBT/T3_5 1 Tf1.92 0 0 -11.52 215.0399 529.9199 Tm()TjETEMC/P <>BDCQ BT/T3_5 1 Tf1.92 0 0 -11.52 216.9599 529.9199 Tm(\000\000\000)TjETEMC/P <>BDCq215.16 611.16 24.72 -150.72 reW* nBT/T3_5 1 Tf1.92 0 0 -11.52 230.3999 529.9199 Tm(\000\000)TjETEMC/P <>BDCQ q215.16 611.16 24.72 -150.72 reW* nBT/T3_5 1 Tf1.92 0 0 -11.52 215.0399 518.3999 Tm()TjETEMC/P <>BDCQ BT/T3_5 1 Tf1.92 0 0 -11.52 216.9598 518.3999 Tm(\000\000\000)TjETEMC/P <>BDCq215.16 611.16 24.72 -150.72 reW* nBT/T3_5 1 Tf1.92 0 0 -11.52 230.3998 518.3999 Tm(\000\000)TjETEMC/P <>BDCQ q215.16 611.16 24.72 -150.72 reW* nBT/T3_5 1 Tf1.92 0 0 -11.52 215.0398 506.8799 Tm()TjETEMC/P <>BDCQ BT/T3_5 1 Tf1.92 0 0 -11.52 216.9598 506.8799 Tm(\000\000\000)TjETEMC/P <>BDCq215.16 611.16 24.72 -150.72 reW* nBT/T3_5 1 Tf1.92 0 0 -11.52 230.3998 506.8799 Tm(\000\000)TjETEMC/P <>BDCQ q215.16 611.16 24.72 -150.72 reW* nBT/T3_5 1 Tf1.92 0 0 -11.52 215.0398 495.3599 Tm()TjETEMC/P <>BDCQ BT/T3_5 1 Tf1.92 0 0 -11.52 216.9598 495.3599 Tm(\000\000\000)TjETEMC/P <>BDCq215.16 611.16 24.72 -150.72 reW* nBT/T3_5 1 Tf1.92 0 0 -11.52 230.3998 495.3599 Tm(\000\000)TjETEMC/P <>BDCQ q215.16 611.16 24.72 -150.72 reW* nBT/T3_5 1 Tf1.92 0 0 -11.52 215.0398 483.8399 Tm()TjETEMC/P <>BDCQ BT/T3_5 1 Tf1.92 0 0 -11.52 216.9598 483.8399 Tm(\000\000\000)TjETEMC/P <>BDCq215.16 611.16 24.72 -150.72 reW* nBT/T3_5 1 Tf1.92 0 0 -11.52 230.3998 483.8399 Tm(\000\000)TjETEMC/P <>BDCQ q215.16 611.16 24.72 -150.72 reW* nBT/T3_5 1 Tf1.92 0 0 -11.52 215.0398 472.3199 Tm()TjETEMC/P <>BDCQ BT/T3_5 1 Tf1.92 0 0 -11.52 216.9598 472.3199 Tm(\000\000\000)TjETEMC/P <>BDCq215.16 611.16 24.72 -150.72 reW* nBT/T3_5 1 Tf1.92 0 0 -11.52 230.3998 472.3199 Tm(\000\000)TjETEMC/P <>BDCQ q215.16 611.16 24.72 -150.72 reW* nBT/T3_5 1 Tf1.92 0 0 -11.52 215.0398 460.7999 Tm(\000\000\000\000\000\000)TjETEMC/Shape <>BDCQ 215.16 611.16 24.72 -150.72 reS1 0 0 scn276.9 553.2 24.72 -92.76 refEMC/P <>BDCq276.9 553.2 24.72 -92.76 reW* n1 1 1 scnBT/T3_6 1 Tf1.92 0 0 -11.52 276.48 564.48 Tm(\000\000\000\000\000\000\000 )TjETEMC/P <>BDCQ 1 1 1 scnBT/T3_6 1 Tf1.92 0 0 -11.52 278.3999 552.96 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q276.9 553.2 24.72 -92.76 reW* nBT/T3_6 1 Tf1.92 0 0 -11.52 276.4799 541.44 Tm()TjETEMC/P <>BDCQ BT/T3_6 1 Tf1.92 0 0 -11.52 278.3999 541.4399 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q276.9 553.2 24.72 -92.76 reW* nBT/T3_6 1 Tf1.92 0 0 -11.52 276.4799 529.9199 Tm()TjETEMC/P <>BDCQ BT/T3_6 1 Tf1.92 0 0 -11.52 278.3999 529.92 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q276.9 553.2 24.72 -92.76 reW* nBT/T3_6 1 Tf1.92 0 0 -11.52 276.4799 518.4 Tm()TjETEMC/P <>BDCQ BT/T3_6 1 Tf1.92 0 0 -11.52 278.3998 518.4 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q276.9 553.2 24.72 -92.76 reW* nBT/T3_6 1 Tf1.92 0 0 -11.52 276.4799 506.88 Tm()TjETEMC/P <>BDCQ BT/T3_6 1 Tf1.92 0 0 -11.52 278.3998 506.88 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q276.9 553.2 24.72 -92.76 reW* nBT/T3_6 1 Tf1.92 0 0 -11.52 276.4798 495.36 Tm()TjETEMC/P <>BDCQ BT/T3_6 1 Tf1.92 0 0 -11.52 278.3998 495.36 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q276.9 553.2 24.72 -92.76 reW* nBT/T3_6 1 Tf1.92 0 0 -11.52 276.4798 483.84 Tm()TjETEMC/P <>BDCQ BT/T3_6 1 Tf1.92 0 0 -11.52 278.3998 483.8399 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q276.9 553.2 24.72 -92.76 reW* nBT/T3_6 1 Tf1.92 0 0 -11.52 276.4798 472.3199 Tm()TjETEMC/P <>BDCQ BT/T3_6 1 Tf1.92 0 0 -11.52 278.3997 472.3199 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q276.9 553.2 24.72 -92.76 reW* nBT/T3_6 1 Tf1.92 0 0 -11.52 276.4797 460.7999 Tm(\000\000\000\000\000\000\000 \000\000\000\000\000\000\000 )TjETEMC/P <>BDCQ 1 1 1 scnBT/T3_7 1 Tf1.92 0 0 -11.52 339.8399 541.4399 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q338.58 546.42 24.6 -85.98 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 337.92 529.9199 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 339.8399 529.92 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q338.58 546.42 24.6 -85.98 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 337.9199 518.4 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 339.8399 518.4 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q338.58 546.42 24.6 -85.98 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 337.9199 506.88 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 339.8398 506.88 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q338.58 546.42 24.6 -85.98 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 337.9199 495.36 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 339.8398 495.36 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q338.58 546.42 24.6 -85.98 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 337.9198 483.84 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 339.8398 483.8399 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q338.58 546.42 24.6 -85.98 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 337.9198 472.3199 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 339.8398 472.3199 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q338.58 546.42 24.6 -85.98 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 337.9198 460.7999 Tm(\000\000\000\000\000\000\000 \000\000\000\000\000\000\000 )TjETEMC/P <>BDCQ 1 1 1 scnBT/T3_7 1 Tf1.92 0 0 -11.52 401.2799 506.88 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q400.2 512.7 24.72 -52.26 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 399.36 495.36 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 401.2799 495.36 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q400.2 512.7 24.72 -52.26 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 399.3599 483.84 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 401.2799 483.8399 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q400.2 512.7 24.72 -52.26 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 399.3599 472.3199 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 401.2798 472.3199 Tm(\000\000\000\000 \000\000)TjETEMC/P <>BDCQ q400.2 512.7 24.72 -52.26 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 399.3599 460.7999 Tm(\000\000\000\000\000\000\000 0.00.51.01.52.02.53.03.54.0#1#2#3#5#7#8MixtureRut Depth (mm)/ESALs x 10-6NA Figure 4-1: Field Rut Depth per ESALs 4.3 Servopac Gyratory Compactor Results The mixtures were compacted in the Servopac Gyratory Compactor to 200 gyrations at 1.25 degrees and also at 2.5 degrees and the gyratory shear and specimen height for each cycle were recorded for each mixture. The Servopac has been identified to compact HMA samples to a density similar to that obtained in the field. Generally, initial compaction begins to orient the sample into their relative stable positions as they come close together and into contact with each other. There is increase in density and gyratory shear but reduction in the air voids at initial compaction. Compaction in the Servopac up to air voids of about 8% or 7% compares with end of field compaction for the mixture or before the road is open to traffic. As the road is open to traffic, the pavement undergoes densification under traffic loading and this is comparable to

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41 compaction in the Servopac between air voids of 7% and 4%. The pavement may experience rutting under channelized traffic at this stage. This may stabilize afterwards for stable mixtures, but for poor or unstable mixtures the rate of rutting may be rapid and might not stabilize. For most unstable mixtures there may be a continual drop in air voids below 3% and a corresponding drop in the gyratory shear may be observed which may be a sign of instability of a mixture. 4.3.1 Gyratory Shear The gyratory shear from the Sevopac at each cycle of gyration for each project compacted at 1.25 degrees is shown in Figure 4-2. There is an increase in the gyratory shear with the cycle of gyrations but no drop in shear was observed for 200 numbers of gyrations. A higher gyratory shear value of approximately 600 kPa was observed for mixtures #1 and #2, followed by a gyratory shear of approximately 550 kPa for mixtures #5, #7 and #8, and 530 kPa for mixture #3. The importance of the direct gyratory shear measured from the Servopac is not yet clear and does not directly relate to field rutting performance. The observation, however, is that the mixtures #1 and #2 which performed poorly in the field had high gyratory shear values whiles the other mixtures had low gyratory shear. The change in gyratory shear per cycle obtained from the slope of the gyratory shear versus number of cycles, plotted on a semi-logarithm scale, is determined for all the projects. The change in gyratory shear per cycle is a measure of the mixtures’ resistance to deformation under increasing compactive effort. A higher slope represents a higher resistance to deformation and therefore a better resistance to rutting. In Figure 4-4 a plot of the gyratory shear and the number of cycles is shown for air voids between 7% and 4% to represent the shear resistance of the mixtures within the traffic densification zone as

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42 measured by the Servopac. It is observed from this plot that the slope or gyratory shear resistance is higher for mixture #3 (24.44 kPa/cycle), followed by mixture #5 and #8 (22.43 and 21.69 kPa/cycle respectively), mixtures #2, #1 and #7 are low (20.25, 19.94 and 17.79 kPa/cycle respectively. These may tend to indicate that mixture #3 has better rutting performance followed by project #5 with mixtures #1, #2 and #7 being poor rutting performers. This ranking correlates slightly with the field rutting performance for the mixtures, except for mixture #7 that is in contrast to expected trend, because it has good field rutting performance. This deviation must be investigated further to ascertain why the observation is different for #7. However, it is important to note that mixture #7 is a fine mix unlike the other mixtures, which are coarse mixes, and it was also designed for a lower traffic level 4 compared to the other mixtures, which were designed for traffic level 5, so it may probably not be appropriate to compare them on the same basis. The change in gyratory shear per cycle for mixture #M1 will be discussed in a later section because no field data is available for comparison. The gyratory shear from the samples compacted at 2.5 degrees, shown in Figure 4-3, followed almost the same trend for all the projects but they were slightly higher values than those obtained for 1.25 degrees. The change in gyratory shear per cycle obtained for samples compacted at 2.5 degrees, however, did not show any logical trend as for the mixtures. 4.3.2 Gyratory Shear and Air Voids For samples compacted at both 1.25 and 2.5 degrees, gyratory shear increases with decreasing air voids for all the mixtures. In figure 4-5 it is realized that the gyratory shear is higher for mixtures #1 and #2 for a particular air void content followed by mixtures #5, #7and #8 whiles mixture #3 has lower gyratory shear for similar air voids.

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43 This may be a direct reflection of the trend observed in the relationship between gyratory shear and the number of cycles where poor mixtures showed higher gyratory shear while good mixtures had relatively low gyratory shear. 4.4 Asphalt Pavement Analyzer (APA) Results Mixtures were tested with the APA, which is used as an indirect measure of field rutting performance. The samples used were 150mm diameter cylindrical specimens compacted to approximately 7% air voids. They were maintained at a temperature of 60C in the APA chamber for at least six hours before the test commenced. Two replicates for each mixture were tested for 8000 numbers of wheel strokes and their rut depths were measured and averaged. Table 4-2 shows the rut depths at the end of 8000 strokes or cycles, and other mixture properties of the samples. The APA rut depths measured from this study tend to show that mixtures #3 and #5 are most resistant to rutting because they have lower average rut depths of 3.18mm and 3.98 respectively, (see Figure 4-8). On the other hand mixtures #1, #2, and #7 had higher rut depths of 7.1mm, 6.55mm and 7.6mm respectively and, therefore, may be considered as least resistant to rutting compared with mixtures #3 and #5. Mixture #8 is in the mid-range with average rut depth of 5.5mm, which may be considered as better than mixtures #1, #2 and #7. APA rut depth measured for mixture #M1 will be discussed later, but may be referenced where appropriate, because field data is not available.

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44 400450500550600650050100150200250No. of Cycles Gs (kpa) #1 #2 #7 #5 #3 #8 #M1#M1#2#1#8#7#5#3 Figure 4-2: Gyratory Shear vrs Number of Cycles for 1.25 Degrees in the Servopac

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45 500520540560580600620640050100150200250No. of Cycles Gs #1 #2 #7 #5 #3#2#1#5#7#3 Figure 4-3: Gyratory Shear vs Number of Cycles for 2.5 Degrees in the Servopac

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46 = 24.441Ln(x) + 393.21R2 = 0.9968y2 = 20.254Ln(x) + 493.09R2 = 0.9977 = 22.431Ln(x) + 431.42R2 = 0.9988 = 17.789Ln(x) + 461.39R2 = 0.9981y8 = 21.685Ln(x) + 450.82R2 = 0.9983y1= 19.946Ln(x) + 504.77R2 = 0.9928= 20.359Ln(x) + 498.66R2 = 0.9967400.0450.0500.0550.0600.0650.01101001000No. of C y cles ( lo g) Gs (kpa) #1 #2 #7 #5 #3 #8 #M1 Lo g #1#M1 #2#8#7#5#3 yM1 y7 y5 y3 Figure 4-4: Gyratory Shear vrs Log of Cycles for Gyrations Between Air Voids of 7%-4% at 1.25 Degrees.

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47 400.0450.0500.0550.0600.0650.00.05.010.015.020.025.030. 0 Air Voids Gs #1 #2 #7 #5 #3 #8 #M1 Figure 4-5: Gyratory Shear vrs Air Voids at 1.25 Degrees in the Servopac

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48 75808590951001101001000No. of Cycles %Gmm #1 #2 #7 #5 #3 #8 #M1 Figure 4-6: Percent G mm vs Number of Cycles for 1.25 Degrees in the Servopac

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49 0.05.010.015.020.025.030.0050100150200250No. of CyclesAir Voids (%) #1 #2 #3 #5 #7 #8 #M1 Figure 4-7: Percent Air Voids vs Number of Cycles for 1.25 Degrees in the Servopac

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50 Table 4-2: APA Specimen Properties and Rut Depths #1 #2 #3 #5 #7 #8 #M1 Specimen 1 2 1 2 1 2 1 2 1 2 1 2 1 2 AC % 5.5 5.5 4.9 4.9 8.4 8.4 6.8 6.8 6.9 6.9 6.0 6.0 5.5 5.5 Air Void % 6.8 7.0 6.34 6.62 7.24 7.15 6.9 6.9 6.6 6.86 6.5 6.8 7.04 6.61 Rut Depth (mm) 7.5 6.8 6.5 6.6 2.9 3.5 3.8 4.2 7.1 8.1 4.95 6.1 8.9 7.2 Avg Rut Depth (mm) 7.10 6.55 3.18 3.98 7.60 5.50 8.05 \000\000\000\000\000\000)TjETEMC/P <>BDCQ q137.4 522.72 22.32 -186.78 reW* n0.6 0.6 1 scnBT/T3_7 1 Tf1.92 0 0 -11.52 136.32 518.4 Tm()TjETEMC/P <>BDCQ 0.6 0.6 1 scnBT/T3_7 1 Tf1.92 0 0 -11.52 138.24 518.4 Tm(\000\000\000)TjETEMC/P <>BDCq137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 151.68 518.4 Tm(\000\000)TjETEMC/P <>BDCQ q137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 136.32 506.88 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 138.2399 506.88 Tm(\000\000\000)TjETEMC/P <>BDCq137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 151.6799 506.88 Tm(\000\000)TjETEMC/P <>BDCQ q137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 136.3199 495.36 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 138.2399 495.36 Tm(\000\000\000)TjETEMC/P <>BDCq137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 151.6799 495.36 Tm(\000\000)TjETEMC/P <>BDCQ q137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 136.3199 483.84 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 138.2399 483.8399 Tm(\000\000\000)TjETEMC/P <>BDCq137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 151.6799 483.8399 Tm(\000\000)TjETEMC/P <>BDCQ q137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 136.3199 472.3199 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 138.2399 472.3199 Tm(\000\000\000)TjETEMC/P <>BDCq137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 151.6799 472.3199 Tm(\000\000)TjETEMC/P <>BDCQ q137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 136.3199 460.7999 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 138.2399 460.7999 Tm(\000\000\000)TjETEMC/P <>BDCq137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 151.6799 460.7999 Tm(\000\000)TjETEMC/P <>BDCQ q137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 136.3199 449.2799 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 138.2399 449.2799 Tm(\000\000\000)TjETEMC/P <>BDCq137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 151.6799 449.2799 Tm(\000\000)TjETEMC/P <>BDCQ q137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 136.3199 437.7599 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 138.2399 437.7599 Tm(\000\000\000)TjETEMC/P <>BDCq137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 151.6799 437.7599 Tm(\000\000)TjETEMC/P <>BDCQ q137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 136.3199 426.2399 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 138.2399 426.2399 Tm(\000\000\000)TjETEMC/P <>BDCq137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 151.6798 426.2399 Tm(\000\000)TjETEMC/P <>BDCQ q137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 136.3198 414.7199 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 138.2398 414.7199 Tm(\000\000\000)TjETEMC/P <>BDCq137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 151.6798 414.7199 Tm(\000\000)TjETEMC/P <>BDCQ q137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 136.3198 403.1999 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 138.2398 403.1999 Tm(\000\000\000)TjETEMC/P <>BDCq137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 151.6798 403.1999 Tm(\000\000)TjETEMC/P <>BDCQ q137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 136.3198 391.6799 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 138.2398 391.6799 Tm(\000\000\000)TjETEMC/P <>BDCq137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 151.6798 391.6799 Tm(\000\000)TjETEMC/P <>BDCQ q137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 136.3198 380.1599 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 138.2398 380.1599 Tm(\000\000\000)TjETEMC/P <>BDCq137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 151.6798 380.1599 Tm(\000\000)TjETEMC/P <>BDCQ q137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 136.3198 368.6399 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 138.2398 368.6399 Tm(\000\000\000)TjETEMC/P <>BDCq137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 151.6798 368.6399 Tm(\000\000)TjETEMC/P <>BDCQ q137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 136.3198 357.1199 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 138.2398 357.1199 Tm(\000\000\000)TjETEMC/P <>BDCq137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 151.6798 357.1199 Tm(\000\000)TjETEMC/P <>BDCQ q137.4 522.72 22.32 -186.78 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 136.3198 345.5999 Tm(\000\000\000\000\000\000)TjETEMC/Shape <>BDCQ 0 0 1 SCN0.9 w 0 j 0 J 137.4 522.72 22.32 -186.78 reS1 1 1 scn193.14 508.2 22.26 -172.26 refEMC/P <>BDCq193.14 508.2 22.26 -172.26 reW* n0.6 0.6 1 scnBT/T3_8 1 Tf1.92 0 0 -11.52 192 518.4 Tm(\000\000\000\000\000\000)TjETEMC/P <>BDCQ q193.14 508.2 22.26 -172.26 reW* n0.6 0.6 1 scnBT/T3_8 1 Tf1.92 0 0 -11.52 192 506.88 Tm()TjETEMC/P <>BDCQ 0.6 0.6 1 scnBT/T3_8 1 Tf1.92 0 0 -11.52 193.92 506.88 Tm(\000\000\000)TjETEMC/P <>BDCq193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 207.36 506.88 Tm(\000\000)TjETEMC/P <>BDCQ q193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 192 495.36 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 193.92 495.36 Tm(\000\000\000)TjETEMC/P <>BDCq193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 207.36 495.36 Tm(\000\000)TjETEMC/P <>BDCQ q193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 192 483.84 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 193.9199 483.8399 Tm(\000\000\000)TjETEMC/P <>BDCq193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 207.3599 483.8399 Tm(\000\000)TjETEMC/P <>BDCQ q193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 191.9999 472.3199 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 193.9199 472.3199 Tm(\000\000\000)TjETEMC/P <>BDCq193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 207.3599 472.3199 Tm(\000\000)TjETEMC/P <>BDCQ q193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 191.9999 460.7999 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 193.9199 460.7999 Tm(\000\000\000)TjETEMC/P <>BDCq193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 207.3599 460.7999 Tm(\000\000)TjETEMC/P <>BDCQ q193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 191.9999 449.2799 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 193.9199 449.2799 Tm(\000\000\000)TjETEMC/P <>BDCq193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 207.3599 449.2799 Tm(\000\000)TjETEMC/P <>BDCQ q193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 191.9999 437.7599 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 193.9199 437.7599 Tm(\000\000\000)TjETEMC/P <>BDCq193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 207.3599 437.7599 Tm(\000\000)TjETEMC/P <>BDCQ q193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 191.9999 426.2399 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 193.9199 426.2399 Tm(\000\000\000)TjETEMC/P <>BDCq193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 207.3599 426.2399 Tm(\000\000)TjETEMC/P <>BDCQ q193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 191.9999 414.7199 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 193.9198 414.7199 Tm(\000\000\000)TjETEMC/P <>BDCq193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 207.3598 414.7199 Tm(\000\000)TjETEMC/P <>BDCQ q193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 191.9998 403.1999 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 193.9198 403.1999 Tm(\000\000\000)TjETEMC/P <>BDCq193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 207.3598 403.1999 Tm(\000\000)TjETEMC/P <>BDCQ q193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 191.9998 391.6799 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 193.9198 391.6799 Tm(\000\000\000)TjETEMC/P <>BDCq193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 207.3598 391.6799 Tm(\000\000)TjETEMC/P <>BDCQ q193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 191.9998 380.1599 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 193.9198 380.1599 Tm(\000\000\000)TjETEMC/P <>BDCq193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 207.3598 380.1599 Tm(\000\000)TjETEMC/P <>BDCQ q193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 191.9998 368.6399 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 193.9198 368.6399 Tm(\000\000\000)TjETEMC/P <>BDCq193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 207.3598 368.6399 Tm(\000\000)TjETEMC/P <>BDCQ q193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 191.9998 357.1199 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 193.9198 357.1199 Tm(\000\000\000)TjETEMC/P <>BDCq193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 207.3598 357.1199 Tm(\000\000)TjETEMC/P <>BDCQ q193.14 508.2 22.26 -172.26 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 191.9998 345.5999 Tm(\000\000\000\000\000\000)TjETEMC/Shape <>BDCQ 193.14 508.2 22.26 -172.26 reS1 1 1 scn248.82 419.58 22.32 -83.64 refEMC/P <>BDCq248.82 419.58 22.32 -83.64 reW* n0.6 0.6 1 scnBT/T3_9 1 Tf1.92 0 0 -11.52 247.68 426.24 Tm(\000\000\000\000\000\000)TjETEMC/P <>BDCQ q248.82 419.58 22.32 -83.64 reW* n0.6 0.6 1 scnBT/T3_9 1 Tf1.92 0 0 -11.52 247.68 414.72 Tm()TjETEMC/P <>BDCQ 0.6 0.6 1 scnBT/T3_9 1 Tf1.92 0 0 -11.52 249.5999 414.72 Tm(\000\000\000)TjETEMC/P <>BDCq248.82 419.58 22.32 -83.64 reW* nBT/T3_9 1 Tf1.92 0 0 -11.52 263.0399 414.72 Tm(\000\000)TjETEMC/P <>BDCQ q248.82 419.58 22.32 -83.64 reW* nBT/T3_9 1 Tf1.92 0 0 -11.52 247.6799 403.2 Tm()TjETEMC/P <>BDCQ BT/T3_9 1 Tf1.92 0 0 -11.52 249.5999 403.2 Tm(\000\000\000)TjETEMC/P <>BDCq248.82 419.58 22.32 -83.64 reW* nBT/T3_9 1 Tf1.92 0 0 -11.52 263.0399 403.2 Tm(\000\000)TjETEMC/P <>BDCQ q248.82 419.58 22.32 -83.64 reW* nBT/T3_9 1 Tf1.92 0 0 -11.52 247.6799 391.68 Tm()TjETEMC/P <>BDCQ BT/T3_9 1 Tf1.92 0 0 -11.52 249.5999 391.68 Tm(\000\000\000)TjETEMC/P <>BDCq248.82 419.58 22.32 -83.64 reW* nBT/T3_9 1 Tf1.92 0 0 -11.52 263.0399 391.68 Tm(\000\000)TjETEMC/P <>BDCQ q248.82 419.58 22.32 -83.64 reW* nBT/T3_9 1 Tf1.92 0 0 -11.52 247.6799 380.16 Tm()TjETEMC/P <>BDCQ BT/T3_9 1 Tf1.92 0 0 -11.52 249.5999 380.16 Tm(\000\000\000)TjETEMC/P <>BDCq248.82 419.58 22.32 -83.64 reW* nBT/T3_9 1 Tf1.92 0 0 -11.52 263.0399 380.16 Tm(\000\000)TjETEMC/P <>BDCQ q248.82 419.58 22.32 -83.64 reW* nBT/T3_9 1 Tf1.92 0 0 -11.52 247.6799 368.64 Tm()TjETEMC/P <>BDCQ BT/T3_9 1 Tf1.92 0 0 -11.52 249.5998 368.64 Tm(\000\000\000)TjETEMC/P <>BDCq248.82 419.58 22.32 -83.64 reW* nBT/T3_9 1 Tf1.92 0 0 -11.52 263.0398 368.64 Tm(\000\000)TjETEMC/P <>BDCQ q248.82 419.58 22.32 -83.64 reW* nBT/T3_9 1 Tf1.92 0 0 -11.52 247.6798 357.12 Tm()TjETEMC/P <>BDCQ BT/T3_9 1 Tf1.92 0 0 -11.52 249.5998 357.12 Tm(\000\000\000)TjETEMC/P <>BDCq248.82 419.58 22.32 -83.64 reW* nBT/T3_9 1 Tf1.92 0 0 -11.52 263.0398 357.12 Tm(\000\000)TjETEMC/P <>BDCQ q248.82 419.58 22.32 -83.64 reW* nBT/T3_9 1 Tf1.92 0 0 -11.52 247.6798 345.6 Tm(\000\000\000\000\000\000)TjETEMC/Shape <>BDCQ 248.82 419.58 22.32 -83.64 reS1 1 1 scn304.5 440.64 22.2 -104.7 refEMC/P <>BDCq304.5 440.64 22.2 -104.7 reW* n0.6 0.6 1 scnBT/T3_10 1 Tf1.92 0 0 -11.52 303.36 449.28 Tm(\000\000\000\000\000\000)TjETEMC/P <>BDCQ q304.5 440.64 22.2 -104.7 reW* n0.6 0.6 1 scnBT/T3_10 1 Tf1.92 0 0 -11.52 303.36 437.76 Tm()TjETEMC/P <>BDCQ 0.6 0.6 1 scnBT/T3_10 1 Tf1.92 0 0 -11.52 305.2799 437.76 Tm(\000\000\000)TjETEMC/P <>BDCq304.5 440.64 22.2 -104.7 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 318.7199 437.76 Tm(\000\000)TjETEMC/P <>BDCQ q304.5 440.64 22.2 -104.7 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 303.3599 426.24 Tm()TjETEMC/P <>BDCQ BT/T3_10 1 Tf1.92 0 0 -11.52 305.2799 426.24 Tm(\000\000\000)TjETEMC/P <>BDCq304.5 440.64 22.2 -104.7 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 318.7199 426.24 Tm(\000\000)TjETEMC/P <>BDCQ q304.5 440.64 22.2 -104.7 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 303.3599 414.72 Tm()TjETEMC/P <>BDCQ BT/T3_10 1 Tf1.92 0 0 -11.52 305.2799 414.72 Tm(\000\000\000)TjETEMC/P <>BDCq304.5 440.64 22.2 -104.7 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 318.7199 414.72 Tm(\000\000)TjETEMC/P <>BDCQ q304.5 440.64 22.2 -104.7 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 303.3599 403.2 Tm()TjETEMC/P <>BDCQ BT/T3_10 1 Tf1.92 0 0 -11.52 305.2798 403.2 Tm(\000\000\000)TjETEMC/P <>BDCq304.5 440.64 22.2 -104.7 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 318.7198 403.2 Tm(\000\000)TjETEMC/P <>BDCQ q304.5 440.64 22.2 -104.7 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 303.3598 391.68 Tm()TjETEMC/P <>BDCQ BT/T3_10 1 Tf1.92 0 0 -11.52 305.2798 391.68 Tm(\000\000\000)TjETEMC/P <>BDCq304.5 440.64 22.2 -104.7 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 318.7198 391.68 Tm(\000\000)TjETEMC/P <>BDCQ q304.5 440.64 22.2 -104.7 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 303.3598 380.16 Tm()TjETEMC/P <>BDCQ BT/T3_10 1 Tf1.92 0 0 -11.52 305.2798 380.16 Tm(\000\000\000)TjETEMC/P <>BDCq304.5 440.64 22.2 -104.7 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 318.7198 380.16 Tm(\000\000)TjETEMC/P <>BDCQ q304.5 440.64 22.2 -104.7 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 303.3598 368.64 Tm()TjETEMC/P <>BDCQ BT/T3_10 1 Tf1.92 0 0 -11.52 305.2798 368.64 Tm(\000\000\000)TjETEMC/P <>BDCq304.5 440.64 22.2 -104.7 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 318.7198 368.64 Tm(\000\000)TjETEMC/P <>BDCQ q304.5 440.64 22.2 -104.7 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 303.3598 357.12 Tm()TjETEMC/P <>BDCQ BT/T3_10 1 Tf1.92 0 0 -11.52 305.2797 357.12 Tm(\000\000\000)TjETEMC/P <>BDCq304.5 440.64 22.2 -104.7 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 318.7197 357.12 Tm(\000\000)TjETEMC/P <>BDCQ q304.5 440.64 22.2 -104.7 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 303.3597 345.6 Tm(\000\000\000\000\000\000)TjETEMC/Shape <>BDCQ 304.5 440.64 22.2 -104.7 reS1 1 1 scn360.12 535.92 22.26 -199.98 refEMC/P <>BDCq360.12 535.92 22.26 -199.98 reW* n0.6 0.6 1 scnBT/T3_11 1 Tf1.92 0 0 -11.52 359.04 541.4399 Tm(\000\000\000\000\000\000)TjETEMC/P <>BDCQ q360.12 535.92 22.26 -199.98 reW* n0.6 0.6 1 scnBT/T3_11 1 Tf1.92 0 0 -11.52 359.04 529.9199 Tm()TjETEMC/P <>BDCQ 0.6 0.6 1 scnBT/T3_11 1 Tf1.92 0 0 -11.52 360.9599 529.92 Tm(\000\000\000)TjETEMC/P <>BDCq360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 374.3999 529.92 Tm(\000\000)TjETEMC/P <>BDCQ q360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 359.0399 518.4 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 360.9599 518.4 Tm(\000\000\000)TjETEMC/P <>BDCq360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 374.3999 518.4 Tm(\000\000)TjETEMC/P <>BDCQ q360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 359.0399 506.88 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 360.9599 506.88 Tm(\000\000\000)TjETEMC/P <>BDCq360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 374.3999 506.88 Tm(\000\000)TjETEMC/P <>BDCQ q360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 359.0399 495.36 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 360.9598 495.36 Tm(\000\000\000)TjETEMC/P <>BDCq360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 374.3998 495.36 Tm(\000\000)TjETEMC/P <>BDCQ q360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 359.0398 483.84 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 360.9598 483.8399 Tm(\000\000\000)TjETEMC/P <>BDCq360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 374.3998 483.8399 Tm(\000\000)TjETEMC/P <>BDCQ q360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 359.0398 472.3199 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 360.9598 472.3199 Tm(\000\000\000)TjETEMC/P <>BDCq360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 374.3998 472.3199 Tm(\000\000)TjETEMC/P <>BDCQ q360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 359.0398 460.7999 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 360.9598 460.7999 Tm(\000\000\000)TjETEMC/P <>BDCq360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 374.3998 460.7999 Tm(\000\000)TjETEMC/P <>BDCQ q360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 359.0398 449.2799 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 360.9597 449.2799 Tm(\000\000\000)TjETEMC/P <>BDCq360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 374.3997 449.2799 Tm(\000\000)TjETEMC/P <>BDCQ q360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 359.0397 437.7599 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 360.9597 437.7599 Tm(\000\000\000)TjETEMC/P <>BDCq360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 374.3997 437.7599 Tm(\000\000)TjETEMC/P <>BDCQ q360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 359.0397 426.2399 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 360.9597 426.2399 Tm(\000\000\000)TjETEMC/P <>BDCq360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 374.3997 426.2399 Tm(\000\000)TjETEMC/P <>BDCQ q360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 359.0397 414.7199 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 360.9597 414.7199 Tm(\000\000\000)TjETEMC/P <>BDCq360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 374.3997 414.7199 Tm(\000\000)TjETEMC/P <>BDCQ q360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 359.0397 403.1999 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 360.9596 403.1999 Tm(\000\000\000)TjETEMC/P <>BDCq360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 374.3996 403.1999 Tm(\000\000)TjETEMC/P <>BDCQ q360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 359.0396 391.6799 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 360.9596 391.6799 Tm(\000\000\000)TjETEMC/P <>BDCq360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 374.3996 391.6799 Tm(\000\000)TjETEMC/P <>BDCQ q360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 359.0396 380.1599 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 360.9596 380.1599 Tm(\000\000\000)TjETEMC/P <>BDCq360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 374.3996 380.1599 Tm(\000\000)TjETEMC/P <>BDCQ q360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 359.0396 368.6399 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 360.9595 368.6399 Tm(\000\000\000)TjETEMC/P <>BDCq360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 374.3995 368.6399 Tm(\000\000)TjETEMC/P <>BDCQ q360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 359.0395 357.1199 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 360.9595 357.1199 Tm(\000\000\000)TjETEMC/P <>BDCq360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 374.3995 357.1199 Tm(\000\000)TjETEMC/P <>BDCQ q360.12 535.92 22.26 -199.98 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 359.0395 345.5999 Tm(\000\000\000\000\000\000)TjETEMC/Shape <>BDCQ 360.12 535.92 22.26 -199.98 reS1 1 1 scn415.8 480.66 22.32 -144.72 refEMC/P <>BDCq415.8 480.66 22.32 -144.72 reW* n0.6 0.6 1 scnBT/T3_12 1 Tf1.92 0 0 -11.52 414.72 483.84 Tm(\000\000\000\000\000\000)TjETEMC/P <>BDCQ q415.8 480.66 22.32 -144.72 reW* n0.6 0.6 1 scnBT/T3_12 1 Tf1.92 0 0 -11.52 414.72 472.32 Tm()TjETEMC/P <>BDCQ 0.6 0.6 1 scnBT/T3_12 1 Tf1.92 0 0 -11.52 416.64 472.32 Tm(\000\000\000)TjETEMC/P <>BDCq415.8 480.66 22.32 -144.72 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 430.08 472.32 Tm(\000\000)TjETEMC/P <>BDCQ q415.8 480.66 22.32 -144.72 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 414.72 460.8 Tm()TjETEMC/P <>BDCQ BT/T3_12 1 Tf1.92 0 0 -11.52 416.6399 460.8 Tm(\000\000\000)TjETEMC/P <>BDCq415.8 480.66 22.32 -144.72 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 430.0799 460.8 Tm(\000\000)TjETEMC/P <>BDCQ q415.8 480.66 22.32 -144.72 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 414.7199 449.28 Tm()TjETEMC/P <>BDCQ BT/T3_12 1 Tf1.92 0 0 -11.52 416.6399 449.28 Tm(\000\000\000)TjETEMC/P <>BDCq415.8 480.66 22.32 -144.72 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 430.0799 449.28 Tm(\000\000)TjETEMC/P <>BDCQ q415.8 480.66 22.32 -144.72 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 414.7199 437.76 Tm()TjETEMC/P <>BDCQ BT/T3_12 1 Tf1.92 0 0 -11.52 416.6399 437.76 Tm(\000\000\000)TjETEMC/P <>BDCq415.8 480.66 22.32 -144.72 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 430.0799 437.76 Tm(\000\000)TjETEMC/P <>BDCQ q415.8 480.66 22.32 -144.72 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 414.7199 426.24 Tm()TjETEMC/P <>BDCQ BT/T3_12 1 Tf1.92 0 0 -11.52 416.6398 426.24 Tm(\000\000\000)TjETEMC/P <>BDCq415.8 480.66 22.32 -144.72 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 430.0798 426.24 Tm(\000\000)TjETEMC/P <>BDCQ q415.8 480.66 22.32 -144.72 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 414.7198 414.72 Tm()TjETEMC/P <>BDCQ BT/T3_12 1 Tf1.92 0 0 -11.52 416.6398 414.72 Tm(\000\000\000)TjETEMC/P <>BDCq415.8 480.66 22.32 -144.72 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 430.0798 414.72 Tm(\000\000)TjETEMC/P <>BDCQ q415.8 480.66 22.32 -144.72 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 414.7198 403.2 Tm()TjETEMC/P <>BDCQ BT/T3_12 1 Tf1.92 0 0 -11.52 416.6398 403.2 Tm(\000\000\000)TjETEMC/P <>BDCq415.8 480.66 22.32 -144.72 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 430.0798 403.2 Tm(\000\000)TjETEMC/P <>BDCQ q415.8 480.66 22.32 -144.72 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 414.7198 391.68 Tm()TjETEMC/P <>BDCQ BT/T3_12 1 Tf1.92 0 0 -11.52 416.6397 391.68 Tm(\000\000\000)TjETEMC/P <>BDCq415.8 480.66 22.32 -144.72 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 430.0797 391.68 Tm(\000\000)TjETEMC/P <>BDCQ q415.8 480.66 22.32 -144.72 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 414.7197 380.16 Tm()TjETEMC/P <>BDCQ BT/T3_12 1 Tf1.92 0 0 -11.52 416.6397 380.16 Tm(\000\000\000)TjETEMC/P <>BDCq415.8 480.66 22.32 -144.72 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 430.0797 380.16 Tm(\000\000)TjETEMC/P <>BDCQ q415.8 480.66 22.32 -144.72 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 414.7197 368.64 Tm()TjETEMC/P <>BDCQ BT/T3_12 1 Tf1.92 0 0 -11.52 416.6397 368.64 Tm(\000\000\000)TjETEMC/P <>BDCq415.8 480.66 22.32 -144.72 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 430.0797 368.64 Tm(\000\000)TjETEMC/P <>BDCQ q415.8 480.66 22.32 -144.72 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 414.7197 357.12 Tm()TjETEMC/P <>BDCQ BT/T3_12 1 Tf1.92 0 0 -11.52 416.6396 357.12 Tm(\000\000\000)TjETEMC/P <>BDCq415.8 480.66 22.32 -144.72 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 430.0797 357.12 Tm(\000\000)TjETEMC/P <>BDCQ q415.8 480.66 22.32 -144.72 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 414.7197 345.6 Tm(\000\000\000\000\000\000)TjETEMC/Shape <>BDCQ 415.8 480.66 22.32 -144.72 reS1 1 1 scn471.48 547.8 22.32 -211.86 refEMC/P <>BDCq471.48 547.8 22.32 -211.86 reW* n0.6 0.6 1 scnBT/T3_13 1 Tf1.92 0 0 -11.52 470.4 552.96 Tm(\000\000\000\000\000\000)TjETEMC/P <>BDCQ q471.48 547.8 22.32 -211.86 reW* n0.6 0.6 1 scnBT/T3_13 1 Tf1.92 0 0 -11.52 470.4 541.44 Tm()TjETEMC/P <>BDCQ 0.6 0.6 1 scnBT/T3_13 1 Tf1.92 0 0 -11.52 472.3199 541.4399 Tm(\000\000\000)TjETEMC/P <>BDCq471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 485.7599 541.4399 Tm(\000\000)TjETEMC/P <>BDCQ q471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 470.3999 529.9199 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 472.3199 529.92 Tm(\000\000\000)TjETEMC/P <>BDCq471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 485.7599 529.92 Tm(\000\000)TjETEMC/P <>BDCQ q471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 470.3999 518.4 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 472.3199 518.4 Tm(\000\000\000)TjETEMC/P <>BDCq471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 485.7599 518.4 Tm(\000\000)TjETEMC/P <>BDCQ q471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 470.3999 506.88 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 472.3199 506.88 Tm(\000\000\000)TjETEMC/P <>BDCq471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 485.7599 506.88 Tm(\000\000)TjETEMC/P <>BDCQ q471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 470.3999 495.36 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 472.3198 495.36 Tm(\000\000\000)TjETEMC/P <>BDCq471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 485.7598 495.36 Tm(\000\000)TjETEMC/P <>BDCQ q471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 470.3998 483.84 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 472.3198 483.8399 Tm(\000\000\000)TjETEMC/P <>BDCq471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 485.7598 483.8399 Tm(\000\000)TjETEMC/P <>BDCQ q471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 470.3998 472.3199 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 472.3198 472.3199 Tm(\000\000\000)TjETEMC/P <>BDCq471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 485.7598 472.3199 Tm(\000\000)TjETEMC/P <>BDCQ q471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 470.3998 460.7999 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 472.3198 460.7999 Tm(\000\000\000)TjETEMC/P <>BDCq471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 485.7598 460.7999 Tm(\000\000)TjETEMC/P <>BDCQ q471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 470.3998 449.2799 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 472.3197 449.2799 Tm(\000\000\000)TjETEMC/P <>BDCq471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 485.7597 449.2799 Tm(\000\000)TjETEMC/P <>BDCQ q471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 470.3997 437.7599 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 472.3197 437.7599 Tm(\000\000\000)TjETEMC/P <>BDCq471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 485.7597 437.7599 Tm(\000\000)TjETEMC/P <>BDCQ q471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 470.3997 426.2399 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 472.3196 426.2399 Tm(\000\000\000)TjETEMC/P <>BDCq471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 485.7596 426.2399 Tm(\000\000)TjETEMC/P <>BDCQ q471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 470.3996 414.7199 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 472.3196 414.7199 Tm(\000\000\000)TjETEMC/P <>BDCq471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 485.7596 414.7199 Tm(\000\000)TjETEMC/P <>BDCQ q471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 470.3996 403.1999 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 472.3196 403.1999 Tm(\000\000\000)TjETEMC/P <>BDCq471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 485.7596 403.1999 Tm(\000\000)TjETEMC/P <>BDCQ q471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 470.3996 391.6799 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 472.3196 391.6799 Tm(\000\000\000)TjETEMC/P <>BDCq471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 485.7596 391.6799 Tm(\000\000)TjETEMC/P <>BDCQ q471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 470.3996 380.1599 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 472.3195 380.1599 Tm(\000\000\000)TjETEMC/P <>BDCq471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 485.7595 380.1599 Tm(\000\000)TjETEMC/P <>BDCQ q471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 470.3995 368.6399 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 472.3195 368.6399 Tm(\000\000\000)TjETEMC/P <>BDCq471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 485.7595 368.6399 Tm(\000\000)TjETEMC/P <>BDCQ q471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 470.3995 357.1199 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 472.3195 357.1199 Tm(\000\000\000)TjETEMC/P <>BDCq471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 485.7595 357.1199 Tm(\000\000)TjETEMC/P <>BDCQ q471.48 547.8 22.32 -211.86 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 470.3995 345.5999 Tm(\000\000\000\000\000\000)TjETEMC/Shape <>BDCQ 471.48 547.8 22.32 -211.86 reS0 0 0 SCN0.06 w 1 j 1 J 120.72 572.7 m120.72 335.94 l119.04 335.94 m120.72 335.94 l119.04 362.28 m120.72 362.28 l119.04 388.56 m120.72 388.56 l119.04 414.9 m120.72 414.9 l119.04 441.18 m120.72 441.18 l119.04 467.52 m120.72 467.52 l119.04 493.8 m120.72 493.8 l119.04 520.14 m120.72 520.14 l119.04 546.42 m120.72 546.42 l119.04 572.7 m120.72 572.7 l120.72 335.94 m510.48 335.94 l120.72 334.26 m120.72 335.94 l176.4 334.26 m176.4 335.94 l232.14 334.26 m232.14 335.94 l287.82 334.26 m287.82 335.94 l343.38 334.26 m343.38 335.94 l399.12 334.26 m399.12 335.94 l454.8 334.26 m454.8 335.94 l510.48 334.26 m510.48 335.94 lSEMC/P <>BDC0 0 0 scnBT/TT4 1 Tf5.52 0 0 5.52 113.4 334.4398 Tm(0123456789#1#2#3#5#7#8#M1MixtureRut Depth (mm) Figure 4-8: APA Rut Depth For 8000 Wheel Strokes APA rut depths at a number of wheel strokes were measured for mixtures #1, #M1, #5 and #8, to follow the rate of rutting for these mixtures. These are shown in figure 4-9. It is observed that for all the mixtures, approximately half of the APA rutting accumulated at the end of 8000 strokes is mobilized within the first 1000 strokes whiles about two-thirds of the rutting is mobilized within 2000 and 2500 strokes. This may be an indication that in practice a greater portion (say two-thirds) of the entire rutting

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51 accumulated within the pavement over its service period is likely to occur very quickly after the first few months of traffic loading. This may be in the form of densification rutting and may not be severe enough to cause hazard, but may be dangerous for motorist if it is high and uneven across the pavement surface. A very high rutting observed after the first few passes of traffic may seem to suggest an unstable mixture especially when the rutting do not begin to stabilize at this stage. This trend is observed in the APA rutting for mixtures #1 and #M1, suggesting that they may be unstable mixtures. Until further testing is performed on some more mixtures it may not be readily feasible to assign numbers to a threshold rut depth in the APA at which a mixture may be considered unstable after a determined number of strokes. However, for the purposes of comparison of the performance of mixtures #1, #M1, #5 and #8 (whose rut rates were monitored), it can be argued from Figure 4-6 that mixtures #1 and #M1 are relatively unstable, while mixtures #5 and #8 appears relatively stable. 4.5 Comparing APA Rutting and Field Rutting APA rutting of the mixtures seems to suggest that mixtures #1, #2 and #7 are poor rut resistant mixtures, whilst mixtures #3 and #5 are relatively good rut resistant mixtures. The field rutting performances also indicated that mixtures #1 and #2 performed poorly whilst mixtures #3, #5 and #7 performed relatively better. Thus by comparison of the APA and the field data, it may be suggested that apart from mixture #7, APA rutting performance for all the other mixtures (#1, #2, #3 and #5), agree with their field rutting performance. The behavior of mixture #7, whereby its field rutting resistance performance is good but on the contrary tends to show poor rutting resistance

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0.001.002.003.004.005.006.007.008.009.000100020003000400050006000700080009000No. Of StrokesRut Depth (mm) #1 #5 #M1 #8 52 Figure 4-9: APA Rut Depth vs Number of Strokes

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53 in the APA, cannot be readily explained without further investigation and possibly additional data (field and laboratory) as pointed out in section 4.3.1. When mixture #7 is removed (because it has to be compared on a different scale), then using the rest of the field data for mixtures #1, #2, #3 and #5 as a basis for presentation, it may be argued that the APA may be a potential laboratory tool for identifying the mixture rutting performance in the field, even though more data is required to make a strong accession of this fact. This point will be discussed again in more details in a later section of this chapter. 4.6 Gyratory Testing Machine (GTM) Results All the mixtures were tested with the GTM at 275F and a vertical pressure of 120 psi. The samples that were tested in a 100 mm diameter cylindrical mould were compacted up to equilibrium density of less than or equal to 0.008 g/cm 3 per 50 cycles. Gyratory shear (G s ) and the Gyratory stability index (GSI) were measured for all three replicate samples that were tested for each mixture and their averages were computed and compared to determine the differences in their shear resistances. Figure 4-10 shows the gyratory shear against the number of cycles for all the mixtures. The gyratory shear of the GTM seems to show no relation with the field performance of the mixtures and no trend of essence was observed for these mixtures. However, the only observation is that all the mixtures, apart from mixture #1, had gyratory shear of about 50 psi or more. Mixture #1 alone had a gyratory shear of less than 40 psi. It is believed that the gyratory shear measured during the compaction at high temperatures is primarily a measure of aggregate properties, since the viscosity of the asphalt is low and the mixture has little cohesion.

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54 4.6.1 Gyratory Stability Index (GSI) The GSI is the ratio of the final gyratory angle to the intermediate gyratory angle. It is a measure of mixture stability and, therefore, may be related to permanent deformation or rutting resistance. The gyration angle increases during compaction for unstable mixtures due to plastic flow of the asphalt mixture. However, it does not increase significantly for stable mixtures and so typical values of GSI close to 1.0 have been identified for stable mixtures. The increase in the GSI is also an indication of excessive asphalt content and therefore may be used for the selection for maximum asphalt content. Values for the GSI measured for the mixtures indicate that mixtures #3 and #7 had the lowest values of 1.02 and 1.07 respectively, followed by mixtures #5 and #8 with 1.12 and 1.14 respectively. Mixtures #1, #M1 and #2 had comparatively higher GSI values of 1.26, 1.22 and 1.23 respectively, figure 4-11. Therefore, it may be suggested that mixtures #3 and #7 are relatively more stable followed by mixtures #5 and #8 whilst mixtures #1, #M1 and #2 may be considered the least stable or unstable mixtures. There was a significant increase in the gyration angles during the compaction of mixtures #1, #M1 and #2, hence their high GSI values. Even though there is no threshold for the GSI values representing unstable mixtures, values beyond 1.2 may be associated with mixture instability. 4.6.2 Comparing Gyratory Stability Index and Field Rutting The GSI values measured for the mixtures indicate that mixtures #3 and #7 are relatively more stable followed by #5 while mixtures #1 and #2 may be the least stable or unstable mixtures, because of their high GSI. Thus it may be suggested that mixtures #1

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55 and #2 may be considered to have poor rut resistance or are high rutting mixtures whiles mixtures #3, #5 and #7 may be considered to have good rut resistance. The GSI of the mixtures seem to agree with the field rutting performance of the mixtures in that, mixtures #3, #5, and #7 performed better in rutting in the field than mixtures #1 and #2. Even though more data is required to present a strong case in terms of correlating GSI with field rutting and possibly identifying rutting performance using GSI, it may be enough to make a suggestion that GSI may be a potential index for predicting the rutting performance of Superpave mixtures and, therefore, has to be further investigated. 4.7 The Superpave VMA Criteria and Mixture Rutting Performance The Superpave volumetric criteria specify a minimum VMA value of 14 for 12.5mm nominal maximum size mixtures and 15 for 9.5mm nominal maximum size mixtures. Mixtures #1 and #5, which are both 9.5mm nominal maximum size mixtures were designed and tested at VMA values below their required values (with same gradation) to determine the effects of meeting VMA criteria or not meeting the VMA criteria on the rutting resistance of mixtures. Mixtures meeting the VMA criteria were also tested for these two mixtures. Volumetric properties for the different mixtures are given in Table 4-3. Table 4-3: Properties for Mix #1 and Mix #5 at N des #1 #5 Mix A B A B %AC 4.7 5.5 6.9 6.8 %Air Voids 4.19 4.07 4.39 4.56 %VMA 14.16* 15.47 14.56* 15.00 %VFA 70.40 73.73 69.82 68.20 *Failed criterion

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56 0.010.020.030.040.050.060.070.00100200300400500600700No. OF GYRATIONSGYRATORY SHEAR (psi) #1 #2 #7 #5 #3 #8 #M1#1#2#8#7 #3#5#M1 Figure 4-10: Gyratory Shear vs Number of Cycles in the GTM

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57 \000\000\000\000\000\000 )TjETEMC/P <>BDCQ 1 0 1 scnBT/T3_7 1 Tf1.92 0 0 -11.52 157.44 668.1599 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q156.66 672.84 21.18 -215.34 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 155.52 656.6399 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 157.44 656.6399 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q156.66 672.84 21.18 -215.34 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 155.5199 645.1199 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 157.4399 645.1199 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q156.66 672.84 21.18 -215.34 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 155.5199 633.5999 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 157.4399 633.5999 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q156.66 672.84 21.18 -215.34 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 155.5199 622.0799 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 157.4399 622.08 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q156.66 672.84 21.18 -215.34 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 155.5199 610.56 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 157.4399 610.5599 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q156.66 672.84 21.18 -215.34 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 155.5199 599.0399 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 157.4399 599.0399 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q156.66 672.84 21.18 -215.34 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 155.5199 587.5199 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 157.4399 587.5199 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q156.66 672.84 21.18 -215.34 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 155.5199 575.9999 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 157.4398 575.9999 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q156.66 672.84 21.18 -215.34 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 155.5199 564.4799 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 157.4398 564.4799 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q156.66 672.84 21.18 -215.34 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 155.5198 552.9599 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 157.4398 552.9599 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q156.66 672.84 21.18 -215.34 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 155.5198 541.4399 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 157.4398 541.4399 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q156.66 672.84 21.18 -215.34 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 155.5198 529.9199 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 157.4398 529.9199 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q156.66 672.84 21.18 -215.34 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 155.5198 518.3999 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 157.4398 518.3999 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q156.66 672.84 21.18 -215.34 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 155.5198 506.8799 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 157.4398 506.8799 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q156.66 672.84 21.18 -215.34 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 155.5198 495.3599 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 157.4397 495.3599 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q156.66 672.84 21.18 -215.34 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 155.5197 483.8399 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 157.4397 483.8399 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q156.66 672.84 21.18 -215.34 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 155.5197 472.3199 Tm()TjETEMC/P <>BDCQ BT/T3_7 1 Tf1.92 0 0 -11.52 157.4397 472.3199 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q156.66 672.84 21.18 -215.34 reW* nBT/T3_7 1 Tf1.92 0 0 -11.52 155.5197 460.7999 Tm(\000\000\000\000\000\000 \000\000\000\000\000\000 )TjETEMC/P <>BDCQ 1 0 1 scnBT/T3_8 1 Tf1.92 0 0 -11.52 211.2 656.6399 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q209.7 667.68 21.18 -210.18 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 209.28 645.1199 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 211.2 645.1199 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q209.7 667.68 21.18 -210.18 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 209.28 633.5999 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 211.1999 633.5999 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q209.7 667.68 21.18 -210.18 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 209.2799 622.0799 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 211.1999 622.08 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q209.7 667.68 21.18 -210.18 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 209.2799 610.56 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 211.1999 610.5599 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q209.7 667.68 21.18 -210.18 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 209.2799 599.0399 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 211.1999 599.0399 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q209.7 667.68 21.18 -210.18 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 209.2799 587.5199 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 211.1999 587.5199 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q209.7 667.68 21.18 -210.18 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 209.2799 575.9999 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 211.1999 575.9999 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q209.7 667.68 21.18 -210.18 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 209.2799 564.4799 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 211.1999 564.4799 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q209.7 667.68 21.18 -210.18 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 209.2798 552.9599 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 211.1998 552.9599 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q209.7 667.68 21.18 -210.18 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 209.2798 541.4399 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 211.1998 541.4399 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q209.7 667.68 21.18 -210.18 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 209.2798 529.9199 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 211.1998 529.9199 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q209.7 667.68 21.18 -210.18 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 209.2798 518.3999 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 211.1998 518.3999 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q209.7 667.68 21.18 -210.18 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 209.2798 506.8799 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 211.1998 506.8799 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q209.7 667.68 21.18 -210.18 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 209.2798 495.3599 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 211.1998 495.3599 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q209.7 667.68 21.18 -210.18 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 209.2798 483.8399 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 211.1997 483.8399 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q209.7 667.68 21.18 -210.18 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 209.2798 472.3199 Tm()TjETEMC/P <>BDCQ BT/T3_8 1 Tf1.92 0 0 -11.52 211.1997 472.3199 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q209.7 667.68 21.18 -210.18 reW* nBT/T3_8 1 Tf1.92 0 0 -11.52 209.2797 460.7999 Tm(\000\000\000\000\000\000 \000\000\000\000\000\000 )TjETEMC/P <>BDCQ 1 0 1 scnBT/T3_9 1 Tf1.92 0 0 -11.52 263.0399 622.08 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q262.68 631.8 21.18 -174.3 reW* nBT/T3_9 1 Tf1.92 0 0 -11.52 261.1199 610.56 Tm()TjETEMC/P <>BDCQ BT/T3_9 1 Tf1.92 0 0 -11.52 263.0399 610.5599 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q262.68 631.8 21.18 -174.3 reW* nBT/T3_9 1 Tf1.92 0 0 -11.52 261.1199 599.0399 Tm()TjETEMC/P <>BDCQ BT/T3_9 1 Tf1.92 0 0 -11.52 263.0399 599.0399 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q262.68 631.8 21.18 -174.3 reW* nBT/T3_9 1 Tf1.92 0 0 -11.52 261.1199 587.5199 Tm()TjETEMC/P <>BDCQ BT/T3_9 1 Tf1.92 0 0 -11.52 263.0399 587.5199 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q262.68 631.8 21.18 -174.3 reW* nBT/T3_9 1 Tf1.92 0 0 -11.52 261.1198 575.9999 Tm()TjETEMC/P <>BDCQ BT/T3_9 1 Tf1.92 0 0 -11.52 263.0398 575.9999 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q262.68 631.8 21.18 -174.3 reW* nBT/T3_9 1 Tf1.92 0 0 -11.52 261.1198 564.4799 Tm()TjETEMC/P <>BDCQ BT/T3_9 1 Tf1.92 0 0 -11.52 263.0398 564.4799 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q262.68 631.8 21.18 -174.3 reW* nBT/T3_9 1 Tf1.92 0 0 -11.52 261.1198 552.9599 Tm()TjETEMC/P <>BDCQ BT/T3_9 1 Tf1.92 0 0 -11.52 263.0398 552.9599 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q262.68 631.8 21.18 -174.3 reW* nBT/T3_9 1 Tf1.92 0 0 -11.52 261.1198 541.4399 Tm()TjETEMC/P <>BDCQ BT/T3_9 1 Tf1.92 0 0 -11.52 263.0397 541.4399 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q262.68 631.8 21.18 -174.3 reW* nBT/T3_9 1 Tf1.92 0 0 -11.52 261.1197 529.9199 Tm()TjETEMC/P <>BDCQ BT/T3_9 1 Tf1.92 0 0 -11.52 263.0397 529.9199 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q262.68 631.8 21.18 -174.3 reW* nBT/T3_9 1 Tf1.92 0 0 -11.52 261.1197 518.3999 Tm()TjETEMC/P <>BDCQ BT/T3_9 1 Tf1.92 0 0 -11.52 263.0397 518.3999 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q262.68 631.8 21.18 -174.3 reW* nBT/T3_9 1 Tf1.92 0 0 -11.52 261.1197 506.8799 Tm()TjETEMC/P <>BDCQ BT/T3_9 1 Tf1.92 0 0 -11.52 263.0396 506.8799 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q262.68 631.8 21.18 -174.3 reW* nBT/T3_9 1 Tf1.92 0 0 -11.52 261.1196 495.3599 Tm()TjETEMC/P <>BDCQ BT/T3_9 1 Tf1.92 0 0 -11.52 263.0396 495.3599 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q262.68 631.8 21.18 -174.3 reW* nBT/T3_9 1 Tf1.92 0 0 -11.52 261.1196 483.8399 Tm()TjETEMC/P <>BDCQ BT/T3_9 1 Tf1.92 0 0 -11.52 263.0396 483.8399 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q262.68 631.8 21.18 -174.3 reW* nBT/T3_9 1 Tf1.92 0 0 -11.52 261.1196 472.3199 Tm()TjETEMC/P <>BDCQ BT/T3_9 1 Tf1.92 0 0 -11.52 263.0396 472.3199 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q262.68 631.8 21.18 -174.3 reW* nBT/T3_9 1 Tf1.92 0 0 -11.52 261.1196 460.7999 Tm(\000\000\000\000\000\000 \000\000\000\000\000\000 )TjETEMC/P <>BDCQ 1 0 1 scnBT/T3_10 1 Tf1.92 0 0 -11.52 316.7999 645.1199 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q315.72 648.84 21.3 -191.34 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 314.8799 633.5999 Tm()TjETEMC/P <>BDCQ BT/T3_10 1 Tf1.92 0 0 -11.52 316.7999 633.5999 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q315.72 648.84 21.3 -191.34 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 314.8799 622.0799 Tm()TjETEMC/P <>BDCQ BT/T3_10 1 Tf1.92 0 0 -11.52 316.7999 622.08 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q315.72 648.84 21.3 -191.34 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 314.8799 610.56 Tm()TjETEMC/P <>BDCQ BT/T3_10 1 Tf1.92 0 0 -11.52 316.7999 610.5599 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q315.72 648.84 21.3 -191.34 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 314.8799 599.0399 Tm()TjETEMC/P <>BDCQ BT/T3_10 1 Tf1.92 0 0 -11.52 316.7998 599.0399 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q315.72 648.84 21.3 -191.34 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 314.8798 587.5199 Tm()TjETEMC/P <>BDCQ BT/T3_10 1 Tf1.92 0 0 -11.52 316.7998 587.5199 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q315.72 648.84 21.3 -191.34 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 314.8798 575.9999 Tm()TjETEMC/P <>BDCQ BT/T3_10 1 Tf1.92 0 0 -11.52 316.7998 575.9999 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q315.72 648.84 21.3 -191.34 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 314.8798 564.4799 Tm()TjETEMC/P <>BDCQ BT/T3_10 1 Tf1.92 0 0 -11.52 316.7997 564.4799 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q315.72 648.84 21.3 -191.34 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 314.8797 552.9599 Tm()TjETEMC/P <>BDCQ BT/T3_10 1 Tf1.92 0 0 -11.52 316.7997 552.9599 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q315.72 648.84 21.3 -191.34 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 314.8797 541.4399 Tm()TjETEMC/P <>BDCQ BT/T3_10 1 Tf1.92 0 0 -11.52 316.7997 541.4399 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q315.72 648.84 21.3 -191.34 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 314.8797 529.9199 Tm()TjETEMC/P <>BDCQ BT/T3_10 1 Tf1.92 0 0 -11.52 316.7997 529.9199 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q315.72 648.84 21.3 -191.34 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 314.8796 518.3999 Tm()TjETEMC/P <>BDCQ BT/T3_10 1 Tf1.92 0 0 -11.52 316.7996 518.3999 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q315.72 648.84 21.3 -191.34 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 314.8796 506.8799 Tm()TjETEMC/P <>BDCQ BT/T3_10 1 Tf1.92 0 0 -11.52 316.7996 506.8799 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q315.72 648.84 21.3 -191.34 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 314.8796 495.3599 Tm()TjETEMC/P <>BDCQ BT/T3_10 1 Tf1.92 0 0 -11.52 316.7996 495.3599 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q315.72 648.84 21.3 -191.34 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 314.8795 483.8399 Tm()TjETEMC/P <>BDCQ BT/T3_10 1 Tf1.92 0 0 -11.52 316.7995 483.8399 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q315.72 648.84 21.3 -191.34 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 314.8795 472.3199 Tm()TjETEMC/P <>BDCQ BT/T3_10 1 Tf1.92 0 0 -11.52 316.7995 472.3199 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q315.72 648.84 21.3 -191.34 reW* nBT/T3_10 1 Tf1.92 0 0 -11.52 314.8795 460.7999 Tm(\000\000\000\000\000\000 \000\000\000\000\000\000 )TjETEMC/P <>BDCQ 1 0 1 scnBT/T3_11 1 Tf1.92 0 0 -11.52 370.5599 633.5999 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q368.82 640.32 21.24 -182.82 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 368.64 622.0799 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 370.5599 622.08 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q368.82 640.32 21.24 -182.82 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 368.6399 610.56 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 370.5599 610.5599 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q368.82 640.32 21.24 -182.82 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 368.6399 599.0399 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 370.5598 599.0399 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q368.82 640.32 21.24 -182.82 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 368.6399 587.5199 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 370.5598 587.5199 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q368.82 640.32 21.24 -182.82 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 368.6398 575.9999 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 370.5598 575.9999 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q368.82 640.32 21.24 -182.82 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 368.6398 564.4799 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 370.5598 564.4799 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q368.82 640.32 21.24 -182.82 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 368.6398 552.9599 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 370.5598 552.9599 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q368.82 640.32 21.24 -182.82 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 368.6397 541.4399 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 370.5597 541.4399 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q368.82 640.32 21.24 -182.82 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 368.6397 529.9199 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 370.5597 529.9199 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q368.82 640.32 21.24 -182.82 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 368.6397 518.3999 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 370.5597 518.3999 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q368.82 640.32 21.24 -182.82 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 368.6397 506.8799 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 370.5596 506.8799 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q368.82 640.32 21.24 -182.82 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 368.6396 495.3599 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 370.5596 495.3599 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q368.82 640.32 21.24 -182.82 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 368.6396 483.8399 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 370.5596 483.8399 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q368.82 640.32 21.24 -182.82 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 368.6396 472.3199 Tm()TjETEMC/P <>BDCQ BT/T3_11 1 Tf1.92 0 0 -11.52 370.5595 472.3199 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q368.82 640.32 21.24 -182.82 reW* nBT/T3_11 1 Tf1.92 0 0 -11.52 368.6395 460.7999 Tm(\000\000\000\000\000\000 \000\000\000\000\000\000 )TjETEMC/P <>BDCQ 1 0 1 scnBT/T3_12 1 Tf1.92 0 0 -11.52 422.4 645.1199 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q421.86 652.32 21.18 -194.82 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 420.48 633.5999 Tm()TjETEMC/P <>BDCQ BT/T3_12 1 Tf1.92 0 0 -11.52 422.3999 633.5999 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q421.86 652.32 21.18 -194.82 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 420.4799 622.0799 Tm()TjETEMC/P <>BDCQ BT/T3_12 1 Tf1.92 0 0 -11.52 422.3999 622.08 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q421.86 652.32 21.18 -194.82 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 420.4799 610.56 Tm()TjETEMC/P <>BDCQ BT/T3_12 1 Tf1.92 0 0 -11.52 422.3998 610.5599 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q421.86 652.32 21.18 -194.82 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 420.4799 599.0399 Tm()TjETEMC/P <>BDCQ BT/T3_12 1 Tf1.92 0 0 -11.52 422.3998 599.0399 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q421.86 652.32 21.18 -194.82 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 420.4798 587.5199 Tm()TjETEMC/P <>BDCQ BT/T3_12 1 Tf1.92 0 0 -11.52 422.3998 587.5199 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q421.86 652.32 21.18 -194.82 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 420.4798 575.9999 Tm()TjETEMC/P <>BDCQ BT/T3_12 1 Tf1.92 0 0 -11.52 422.3998 575.9999 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q421.86 652.32 21.18 -194.82 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 420.4798 564.4799 Tm()TjETEMC/P <>BDCQ BT/T3_12 1 Tf1.92 0 0 -11.52 422.3997 564.4799 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q421.86 652.32 21.18 -194.82 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 420.4797 552.9599 Tm()TjETEMC/P <>BDCQ BT/T3_12 1 Tf1.92 0 0 -11.52 422.3997 552.9599 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q421.86 652.32 21.18 -194.82 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 420.4797 541.4399 Tm()TjETEMC/P <>BDCQ BT/T3_12 1 Tf1.92 0 0 -11.52 422.3997 541.4399 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q421.86 652.32 21.18 -194.82 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 420.4797 529.9199 Tm()TjETEMC/P <>BDCQ BT/T3_12 1 Tf1.92 0 0 -11.52 422.3997 529.9199 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q421.86 652.32 21.18 -194.82 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 420.4796 518.3999 Tm()TjETEMC/P <>BDCQ BT/T3_12 1 Tf1.92 0 0 -11.52 422.3996 518.3999 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q421.86 652.32 21.18 -194.82 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 420.4796 506.8799 Tm()TjETEMC/P <>BDCQ BT/T3_12 1 Tf1.92 0 0 -11.52 422.3996 506.8799 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q421.86 652.32 21.18 -194.82 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 420.4796 495.3599 Tm()TjETEMC/P <>BDCQ BT/T3_12 1 Tf1.92 0 0 -11.52 422.3996 495.3599 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q421.86 652.32 21.18 -194.82 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 420.4796 483.8399 Tm()TjETEMC/P <>BDCQ BT/T3_12 1 Tf1.92 0 0 -11.52 422.3995 483.8399 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q421.86 652.32 21.18 -194.82 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 420.4795 472.3199 Tm()TjETEMC/P <>BDCQ BT/T3_12 1 Tf1.92 0 0 -11.52 422.3995 472.3199 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q421.86 652.32 21.18 -194.82 reW* nBT/T3_12 1 Tf1.92 0 0 -11.52 420.4795 460.7999 Tm(\000\000\000\000\000\000 \000\000\000\000\000\000 )TjETEMC/P <>BDCQ 1 0 1 scnBT/T3_13 1 Tf1.92 0 0 -11.52 476.1599 656.6399 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q474.9 666 21.18 -208.5 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 474.2399 645.1199 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 476.1599 645.1199 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q474.9 666 21.18 -208.5 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 474.2399 633.5999 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 476.1599 633.5999 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q474.9 666 21.18 -208.5 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 474.2399 622.0799 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 476.1599 622.08 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q474.9 666 21.18 -208.5 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 474.2399 610.56 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 476.1599 610.5599 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q474.9 666 21.18 -208.5 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 474.2398 599.0399 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 476.1598 599.0399 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q474.9 666 21.18 -208.5 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 474.2398 587.5199 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 476.1598 587.5199 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q474.9 666 21.18 -208.5 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 474.2398 575.9999 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 476.1597 575.9999 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q474.9 666 21.18 -208.5 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 474.2397 564.4799 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 476.1597 564.4799 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q474.9 666 21.18 -208.5 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 474.2397 552.9599 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 476.1597 552.9599 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q474.9 666 21.18 -208.5 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 474.2397 541.4399 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 476.1597 541.4399 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q474.9 666 21.18 -208.5 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 474.2397 529.9199 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 476.1596 529.9199 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q474.9 666 21.18 -208.5 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 474.2396 518.3999 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 476.1596 518.3999 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q474.9 666 21.18 -208.5 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 474.2396 506.8799 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 476.1595 506.8799 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q474.9 666 21.18 -208.5 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 474.2396 495.3599 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 476.1595 495.3599 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q474.9 666 21.18 -208.5 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 474.2395 483.8399 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 476.1595 483.8399 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q474.9 666 21.18 -208.5 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 474.2395 472.3199 Tm()TjETEMC/P <>BDCQ BT/T3_13 1 Tf1.92 0 0 -11.52 476.1595 472.3199 Tm(\000\000\000 \000\000)TjETEMC/P <>BDCQ q474.9 666 21.18 -208.5 reW* nBT/T3_13 1 Tf1.92 0 0 -11.52 474.2395 460.7999 Tm(\000\000\000\000\000\000 0.00.10.20.30.40.50.60.70.80.91.01.11.21.31.4#1#2#3#5#7#8#M1MixtureGSI Figure 4-11: Gyratory Stability Index of the Mixtures For the purposes of differentiating between the mixtures, those that failed the VMA requirement will be labeled as A and those that met the requirement will be labeled as B, in this section only. This means that mixtures #1-A and #5-A failed the VMA while mixtures #1-B and #5-B met the VMA. It will immediately be clear that mixture #1-B, was obtained by increasing asphalt content for #1-A from 4.7% to 5.5% in order to meet the VMA requirement. As asphalt content was increased, the air voids reduced slightly from 4.19% to 4.07% and also the VFA increased from 70.4% to 73.73%. The relationships between %AC and %VMA, %Air Voids and %VFA for mixture #1 are shown in Figures 4-12, 4-13 and 4-14 respectively.

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58 Results of tests conducted on the mixtures #1-A and #1-B are shown in Table 4-4. The APA rutting tests performed on the mixtures show that mixture #1-A has a rut depth of 5.0mm and mixture #1-B has a rut depth of 7.1mm. The GTM test also show that mixture #1-A has a GSI value of 1.06 and that of mixture #1-B is 1.26. Therefore both tests, tend to show that mixture #1-A has a high resistance to rutting than mixture #1-B, even though mixture #1-A does not meet the VMA requirement where as mixture #1-B does. 13.514.014.515.015.516.04.54.74.95.15.35.55.7% AC% VMA#1-A#1-B Figure 4-12: Percent AC vs Percent VMA for Mixture #1

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59 44.14.24.54.74.95.15.35.55.7% AC% Air Voids#1-A#1-B Figure 4-13: Percent AC vs Percent Air Voids for Mixture #1 69707172737475764.54.74.95.15.35.55.7% AC% VFA #1-A#1-B Figure 4-14: Percent AC vs Percent VFA for Mixture #1

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60 Table 4-4: Comparing Test Results for Mixture #1-A and #1-B Mix #1-A #1-B APA Rut Depth (mm) 5.0 7.1 GTM Gyratory Stability Index (GSI) 1.06 1.26 Increasing the asphalt content, in order to meet the VMA requirement for #1-B, resulted in a weaker mixture, hence the poor rutting resistance for this mixture. However, the reduction in design air void from 4.19% to 4.07% in the process is good for increasing resistance to moisture damage and aging of the mixture because of lower permeability. It will also be realized that for mixtures #5-A and #5-B, the asphalt content was reduced from 6.9% to 6.8% to meet the VMA requirement at N des . The relationships between %AC and %VMA, %Air Voids and %VFA for mixture #5 are shown in Figures 4-15, 4-16 and 4-17 respectively. As asphalt content was reduced, the air void increased from 4.39% to 4.56% and the VFA also reduced from 69.82% to 68.20%. The results of tests conducted on the mixtures #5-A and #5-B are given in Table 4-5. APA rutting test shows that mixture #5-A has a rut depth of 5.2mm and rut depth of mixture #5-B is 3.98mm. GTM test also shows that mixture #5-A has a GSI value of 1.18 and mixture #5-B has a GSI value of 1.16. These tests, therefore show that mixture #5-B has a high rutting resistance than mixture #5-A, based on an earlier analysis of these tests and field performance of mixtures. Again, it will be realized that a reduction in asphalt content for the same gradation resulted in a better rutting performance of the mixture. However, the increase in air voids (from 4.39% to 4.56%) was not good for resistance to moisture damage and aging of the mixture. There must, therefore, be a tradeoff between achieving high resistance to rutting and high resistance to moisture damage/aging.

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61 Table 4-5: Comparing Test Results for Mixture #5-A and #5-B Mix #5-A #5-B APA Rut Depth (mm) 5.2 3.98 GTM Gyratory Stability Index (GSI) 1.18 1.16 4.8 Aggregate Gradation Effects The effect of gradation on mixture #1 was investigated by modifying the blend to obtain mixture #M1 which had 8% aggregate retained on the sieve instead of 1%. This was done to increase the coarse material of the mix and change the aggregate structure. The gradation of the new blend (#M1) is shown in Figure 4-19. The mixture design and volumetric properties of the new mixture #M1 did not change so much from mixture#1, as the design asphalt content stayed the same (see Table B-1 in appendix B). Samples of mixture #M1 was also tested in the Servopac, APA and in the GTM to determine the rutting resistance of the mixture. Test results obtained for #M1 (Table 4-6) showed that rutting performance for #M1 was similar to that of #1. The mixture showed signs of instability and structural weakness as in #1. It appears that the excess asphalt needed to meet the VMA requirement for mixture #1 tends to push the aggregate particles apart and reduced the aggregate particle contact within the structure. This has rendered changes in the gradation ineffective. Thus aggregate gradation change in mixture #1 did not improve the rutting performance of the mixture as expected. Therefore, gradation may not be the cause of poor rutting performance for mixture #1, but excessive asphalt content. Table 4-6: Comparing Test Results for Mixture #M1 and #1 Mix #1 #M1 Servopac Gyratory Shear resistance 19.95 20.36 APA Rut Depth (mm) 7.1 8.05 GTM Gyratory Stability Index (GSI) 1.26 1.22

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62 Figure 4-16: Percent AC vs Percent Air Voids for Mixture #5 14.014.214.414.614.815.015.26.56.66.76.86.977.17.27.37.4%AC% VMA #5-A#5-B Figure 4-15: Percent AC vs Percent VMA for Mixture #5 3.03.23.43.63.84.04.24.44.64.86.56.66.76.86.977.17.27.37.4%AC% Air Voids #5-B#5-A

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63 Figure 4-17: Percent AC vs Percent VFA for Mixture #5 65.067.069.071.073.075.06.56.66.76.86.977.17.27.37.4%AC% VFA#5-B#5-A 77.079.0 4.9 Predicting Rutting Performance of Mixtures Prediction of mixture performance in the laboratory during design is necessary for sting mixtures have been used to identify mixture behavior and response to loading which may be linked to performance. Among the methods being used are the Superpave Shear Tester, The Wheel Tracking Devices, The Superpave Gyratory Compactor, The Gyratory Testing Machine and many others. In this study three equipments were used to test mixtures to determine their suitability as tools for predicting mixture-rutting performance. The Servopac Gyratory Compactor, the Asphalt Pavement Analyzer and the Gyratory Testing Machine were used to test mixtures whose field rutting performances are known. The performances of the the production of quality mixtures. Various methods of te

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64 Figure 4-18: Gradation Chart Showing Modified Blend #M1 020406080100Sieve Size (mm)^0.45Percent Passing #1 JMF #M10.0750.1500.3000.6001.182.364.759.512.519.0

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65 mixtures in the laboratory were compared with that of the field to determine whether laboratory data correlates with field data and if laboratory data could be used as prediction tests. Figure 4-7 shows a comparison of mixture parameters measured with each of the equipment and their field performance. Table 4-7: Comparing Field and Laboratory Performance Mixture Field Rut Depth per Servopac APA Rut GTM Gyratory No. ESALs Gs/log Cycle Depth Stability Index mm x 10-6 kpa/cycle mm GSI #1 3.45 19.95 7.1 1.26 #2 2.42 20.25 6.55 1.23 #3 1.49 24.44 3.18 1.02 #5 1.38 22.43 3.98 1.12 #7 0.84 17.79 7.6 1.07 4.9.1 The Rate of Change of Gyratory Shear With Cycles from Servopac The mixtures were compacted in the Servopac Gyratory Compactor to 200 gyrations and their gyratory shear plotted against the number of cycles on a logarithm scale for gyrations between 7% to 4% air voids. The slope of the curve is referred to as the rate of change of gyratory shear with cycles, in this study, and it is aasure of the mixture’s resistance to compaction. A higher slope corresponds to a higher resistance to compaction and therefore high resistance to deformation. The rate of change of gyratory shear with cycles measured for the mixtures are compared with the field rutting performance to determine any correlation between the gyratory shear mred from the Servopac and rutting resistance. As discussed in section 4.3.1 of this chapter, the rate of change of gyratory shear with cycles measured in the Servopac followed a specific trend for all the mixtures in the sense that mixtures #3 and #5 which had good field rutting performance had higher gyratory shear resistances than mixtures #1 and #2, which had poor field rutting performances. Mixture #7, which had good field performance but a low meeasu

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66 rate of change of gyratory shear with cycles, is contrary to expectations, but it has to bcompared to other mixtures that are fine and also designed for traffic level 5. If m#7 is eliminated, then a correlation such as shown in figure 4-20 is obtained. The regression coefficient, r is 0.83. More data are certai e ixture nly required to give a reasonable ood step to investigate further rate o gyratitht rutng of Supxtures. level of confidence in the correlation but it is definitely a g into the p ossibility of using the f change of ory shear w cycles to predic ti erpave mi # 1 R2 = 0.6930.511.522.53.54-6 3 019202122232425Gs/log No. of Cycle (kpa/cycle)(Field Rut Depth (mm)/ESALs)x10Figure 4-19: Correlation of the Gs/log No. of Cycles Measured from Servopac With #2 #5 #3 Field Rutting

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67 4.9.2 Asphalt Pavement Analyzer (APA) Rut Depth All the mixtures were tested in the Asphalt Pavement Analyzer at 60C for a totalof 8000 wheel strokes. The hose pressure of the APA was set to 100 psi and with aload of 100 lbs. Rut depths were measured for each of the mixtures compacted to 7% avoids in the Pine gyratory Compactor. The rut depths in the APA were then compared to the field rutting performances of the mixtures for any correlation with the field rutting.As discussed in section 4.4.1, th wheel ir e APA results followed a specific trend for all the mixtures that showed that mixtures #3 and #5 are good rut resistant mixtures while mixtures #1 and #2 are poor rut resistant mixtures. This trend agreed with the field performance of the mixtures, however, mixture # 7 is not considered for this comparison for same reason explained in section 4.8.1, so a correlation such as obtained in the figure 4-21 is obtained. The correlation coefficient, r is 0.92. It is again emphasized that more data is required to give a reasonable level of confidence in this correlation, but it is definitely a good step to investigate further into the possibility of using the APA to predict rutting of Superpave mixtures, as it is already being used by some agencies for this purpose. 4.9.3 Gyratory Testing Machine (GTM) Stability Index The GTM was used to test all the mixtures at a temperature of 275C and gyrated to equilibrium densities, in 100 mm diameter mold, (section 4.5). The gyratory stability inangle, was measured on a gyrograph. The GSI is a measure of mixture stability and, therefore, may be related to permanent deformation or rutting resistance. The GSI values for all the mixtures were measured and compared to the field rutting performances of the mixtures to find out if there is any correlation between the GSI and the rutting resistance dex (GSI), which is the ratio of the final gyratory angle to the intermediate gyratory

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68 of Superpave mixtures. As discussed in section 4.5.1 of this chapter, the GSI values obtaineo redict in in d for all the mixtures followed a particular trend in the sense that, good rut resistance mixtures had lower GSI values whiles poor rut resistance mixtures had relatively higher values, which is a sign of instability. A correlation such as shown in figure 4-22 is obtained for the GSI from the GTM and the field rutting performances of the mixtures. The correlation coefficient, r is 0.87. This is also a reasonable correlation twarrant further investigations into the use of the GSI measured from the GTM to prutting resistance of Superpave mixtures. Of course, it must be emphasized once agahere that, more data and further analysis is required to provide sufficient confidencethis correlation. 22.02.54.0Field Rutting/ESALs x10#1 R = 0.85070.51.03.03.58APA Rut Depth (mm)-6#2 1.5#3 0.0234567#5 Figure 4-20: Correlation of the APA Rut Depth With Field Rutting

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69 R2 = 0.752200.533.511.051.11.151.21.251.3Gyratory Stability Index (GSI)#5#7 11.522.54Field Rutting/ESALs x10-6#1#2#3 Figure 4-21: Correlation of the GTM Gyratory Stability Index With Field Rutting

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CHAPTER 5 CONCLUSIONS 5.1 Overview Superpave mixtures with known field rutting performances were used in this study to evaluate the relationship between laboratory mix properties and rutting resistance of Superpave mixtures. The Job Mix Formulas of these mixtures were reproduced (but without the RAP material) and used for the preparation of mixes in the laboratory; design was based on the Superpave volumetric mix design procedures. The mixtures were tested in three equipments (Servopac Gyratory Compactor, Asphalt Pavement Analyzer and Gyratory Testing Machine) and their measured parameters and mix ture properties were compared with the field performances of these mixtures. 5.2 Summary of Findings Meeting the current Superpave VMA requirement appears to result in over-asphalting for some coarse graded mixtures; consequently these mixtures may have poor rutting resistances even though they may meet the present Superpave volumetric mix criteria. It appears that changes in the aggregate gradation or structure do not significantly affect the rutting performance for mixtures that contain excessive asphalt. This is primarily because the asphalt tends to push the aggregates apart such that there is no effective particle-particle contact between the aggregates. The influence of the asphalt tends to predominantly override that of the aggregates in this case. However, at lower 70

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71 asphalt contents the aggregate may have greater influence on the mixture rutting performance, overriding that of the asphalt. The gyratory shear, Gs measured in the Servopac Gyratory Compactor does not have any apparent direct relationship with rutting resistance of mixtures. However, in this study it was observed that rut-suscs had higher gyratory shear as comarithm r aded Rut depths measured for mixtures tested in the APA seem to have a relationship with rutting resistance of the mixtures. A higher rut depth in the APA corresponds to a low rutting resistance for the mixture, while a relatively low rut depth in the APA also corresponds to a comparatively higher rutting resistance of the mixture. The gyratory shear, Gs measured from the GTM did not show any apparent relationship with the rutting resistance of the mixtures. The gyratory shear seems to measure the aggregate gradation or properties. It responded rapidly to change in gradation irrespective of the excessive asphalt content; a phenomenon not observed in the Servopac Gyratory Compactor or the APA. eptible mixture pared with that of the rut-resistant mixtures. The slope of the graph of gyratory shears vs number of cycles (on a semi-logscale) obtained from the Servopac appears to have a relationship with rutting resistance of mixtures. This slope, referred to as the rate of change of gyratory shear with cycles in this study, is higher for good rut resistant mixtures and relatively lowefor rut-susceptible mixtures. This relationship tends to work better for coarse grmixtures investigated in this study; further investigation is required to ascertain the trend for fine mixtures.

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72 The gyratory stability index, GSI, measured in the GTM, appears to have a relationship with the rutting resistance of the mixtures. It seems that a GSI value of s. 5.3 Recommendations The following recommendations are based on the above findings evolving from this study and other related research efforts. Further study and more data are required to validate the findings and conclusions as well as increase the level of confidence in these findings. The current VMA requirements for Superpave mixtures should be reviewed for some coarse graded mixtures because it forces the use of excessive asphalt for certain coarse-graded mixtures to meet the criteria. The rate of change of gyratory shear with cycles, discussed in Chapter 4 of this report, measured from compaction in the Servopac Gyratory Compactor may be a potential parameter for assessing the rutting resistance of coarse mixtures in the laboratory and, therefore, should be investigated further for this purpose. It must also be investigated for fine mixtures. Rut depth measured from the APA has a potential relationship with the rutting resistance of mixtures and could be used to predict the rutting performance of mixtures in the laboratory. 1.0 corresponds to a stable mixture while a GSI value far exceeding 1.0 may representan unstable mixture. This parameter also gives indication of mixtures with excessive asphalt content because the GSI far exceeds 1.0 for mixtures with overfilled void

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73 The gyratory stability index (GSI) measured from the GTM also has a potenpredict the stability or instability of mixtures and therefore could be used to assess thrutting resistance of mixtures in the laboratory. Mixture #7, which was used as part of this study, should be compacted for traffic level 5 and compared with rutting resistance data for other fine mixtures in order to tial to e get a better understanding of its behavior. Mixresistance predicting parameters evaluated in this report, when field data become ove findings should be validated by further tests and investigations, especially same stretch of roadway section. This will eliminate experimental variables such as different traffic loading, different subgrade/subbase/base support, and different weather conditions that may affect the results. ture #8, also used in this study, can be used to check the reliability of the rutting available. The ab involving field rutting performance data that are obtained from mixtures placed on the

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APPENDIX A ETS AGGREGATE GRADATIONS, PROPERTIES AND BATCH WEIGHT SHE

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Table A-1: Gradations and Specific Gravity of Aggregates for Project #1 Blend #89 Stone 50.0% Aggregate gradation W-10 Scrns 18.7% Sieve Size Sieve, mm mm0.45 W-10 Scrns JMF #89 Stone M-10 Gra 31.3% 3/4" 19.0 3.76 100 100 100 100.0 100 1/2" 12.5 3.12 100 100 100 100.0 100 3/8" 9.5 2.75 100 100 100 100.0 99 #4 4.75 2.02 32 96 99 64.9 64 #8 2.36 1.47 2 73 82 40.3 40 #16 1.18 1.08 1 47 60 28.1 29 #30 0.600 0.79 1 29 45 20.0 21 #50 0.300 0.58 1 15 33 13.6 14 #100 0.150 0.43 1 6 24 9.1 8 #200 0.075 0.31 0.4 2.7 16.3 5.8 5.1 Pan 0 0.00 0 0 0 0.0 0 Bulk Specific Gravity (Gsb) 2.689 2.682 2.700 2.691 2.667 Table A-2: Gradations and Specific Gravity of Aggregates for Project #2 Blend #7 Stone 20.2% #89 Stone 47.9% Aggregate gradations W-10 Scrn 1 21.2% Sieve Size Sieve, mm mm0.45 #7 Stone #89 Stone W-10 Scrn 1 W-10 Scrn 2 10.7% JMF 3/4" 19.0 3.76 100 100 100 100 100.0 100 1/2" 12.5 3.12 90 100 100 100 98.0 98 3/8" 9.5 2.75 48 99 100 100 89.0 89 #4 4.75 2.02 3 29 98 100 46.0 45 #8 2.36 1.47 2 3 73 100 28.0 28 #16 1.18 1.08 2 2 47 100 22.0 22 #30 0.600 0.79 2 2 30 64 14.6 17 #50 0.300 0.58 1 2 18 38 9.0 12 #100 0.150 0.43 1 2 9 19 5.1 7 #200 0.075 0.31 1 1 4 9 2.5 4.9 Pan 0 0.00 0 0 0 0 0.0 0.0 Bulk Specific Gravity (Gsb) 2.693 2.689 2.682 2.743 2.694 2.685 75

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76 Table A-3: Gradations and Specific Gravity of Aggregates for Project #3 Blend S-1-A Stone 19.2% ggregate gradation S-1-B Stone 33.5% Siz e mm m 0.45 A Stone S-1-B Stone 200 Scrns 47.3% JMF 3/4" 193.76 1001 .0 00 100 100.0 100 1/2" 123.12 601 .5 00 100 92.3 94 3/8" 9.2.75 401 5 00 100 88.5 90 75 5 95 67.9 67 36 7 66 34.7 34 #16 1.1.08 6 18 5 45 24.1 25 #30 0.0.79 5 600 5 29 16.4 18 #50 0.0.58 4 300 4 20 11.6 13 100 150 8 5.4 7 200 075 3 4 3.5 4.4 Pan 0 0.000 0 0 0.0 0.0 Bulk Specific Gravity (G sb ). 2.414 2.288 2.317 2.325 2.382 A Sieve Sieve, m S-1#4 4.2.02 6 6 #8 2.1.47 6 #0.0.43 3 3 #0.0.31 3 Table A-4: Gradations and Specific Gravity of Aggregates for Project #5 Blend Stone 62.8% Si eve Size Sieve, m mm0.45 FC-3 Stone Med. Asph. Scrns W-10 Scrns m 16.4% 100 10 0 100 100.0 100 2" .5 12 100 00 100.0 100 8" 5 75 91 00 94.3 94 02 41 00 62.9 64 47 6 2 34.7 34 6 08 4 5 25.1 24 0 00 79 4 8 17.9 19 0 00 58 3 7 12.4 13 00 50 43 3 6.5 8 00 75 31 2 3.0 00 0 0.0 0 Gsb) 1 FC-3 Aggregate gradation Med. Asph. Scrns 20.8% JMF 3/4" 19.0 3.76 1/123.100 1 3/9.2.100 1 #4 4.75 2.100 1 #8 2.36 1.92 7 #11.18 1.73 4 #30.60.52 2 #50.30.37 1 #10.10.15 9 #20.00.5 43.9 Pan 0 0.0 0 Bulk Specific Gravity (2.339 2.471 2.692.418 2.459

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77 Table A-5: Gradations and Specific Gravity of Aggregates for Project #7 B lend 4.5% Aggregate g rS adation -1-B Stone 2.5% ve 0. -A St 1-B S alt S 3.0% F .0 3.76 100 100 100 .5 3.12 74 100 100 3.6 5 2.75 47 92 100 75 2.02 6 37 100 36 1.47 6 6 87 6 .18 1.08 5 5 59 0 600 0.79 5 4 38 0 300 0.58 4 3 22 00 150 0.43 4 3 8 0 5 0.31 3 3 3.5 Pan 0 0.00 0 0 0 0.0 S-1-A Stone 2 1 SieSize Sieve, mm mm45 S-1one S-tone Asphcrns 6 JM 3/4" 19 100.0 100 1/2" 12 995 3/8" 9. 86.0 88 #4 4. 69.1 70 #8 2. 57.0 57 #11 39.0 41 #30. 25.7 30 #50. 15.2 19 #10. 6.4 9 #200.07 3.3 4.2 0.0 Bulk Specific Gravity (Gsb) 2.407 2.407 2.508 2.470 2.49 Table A-6: Gradations and Specific Gravity of Aggregates for Project #8 JMF M ill. Mat. 1 S-A Stone B Stone 50% w Mill crns 10% Siev e mmMill. Mat. -A Stone S-1-B Stone New Mis S Size Sieve, mm 0.45 S-1 ll Scrn and 3/4 " 3.76 100 100 10100 19.0 10 0 0 100 1/2 " 3.12 98 60 100 100 1 12.5 00 94 3/8 " 2.75 95 39 100 100 1 9.5 00 90 #4 2.02 73 7 52 97 1 4.75 00 59 #8 2.36 1.47 59 6 8 65 9 9 3 2 #16 1.08 50 5 3 48 8 1.18 9 25 #3 0 0.79 46 4 3 37 5 0.0 60 0 1 8 #50 0 0.58 40 3 3 26 20 .300 12 #100 0.150 0.43 27 3 2 18 7 7 10% 15% S-1Aggregate gradation NeS 15% #200 0.075 0.31 10.9 3 2 8.7 1 4.5 Pan 0 0.00 0 0 0 0 0 0 Bulk Specific Gravity (Gsb) 2.605 2.420 2.465 2.544 2.630 2.503

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78 Table A-7: Summary of Design JMF and Reproduced Blend of Aggregate Gradations Project No. 1 2 MF Ble nd 0 40.0 40.3 28.0 28.0 21.0 20.0 17.0 14.6 8.0 3 58 7 J MF len d J F F 0 10 0. 1 00. 0 1 00. 0 10 1 00 .0 1 00 1 .0 8 9.0 8 9. 94.0 8 8.0 86. 0 9 0 64.0 62.9 70.0 69.1 59 34.0 5. 24.0 0 13.0 7.0 8.0 3.9 4.5 Sieve Size J BMBlend JMBlendJMF Blend JMF 19.0 100 0100.0 100 100 10 0.0 12.5 100.0 100.0 98.0 98.0 94.0 92.3 100.095.0 93.6 94 00 9.5 99.090.0 88.5 94.3 10 0.0 4.75 64.0 64.9 45.0 46.0 67.0 67.9 2.36 34.0 34.7 34.7 57.0 57.0 32 1.18 29.0 28.1 22.0 22.0 20 24.1 25.141.0 39.0 2 5 0.600 18.0 16.4 19. 17.9 30.0 25.7 18 0.300 14.0 13.6 12.0 9.0 13.0 11.6 12.4 19.0 15.2 12 0.150 9.1 7.0 5.1 5.4 6.59.0 6.4 7 0.075 5.1 5.8 4.9 2.5 4.4 3.5 3.0 4.2 3.3

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79 Figure A-1: Gradation Chart for JMF and Blend of Project No. 1. (9.5mm Nominal size) 060100Sieve Size (mm)^0.45Percent Passing Blen JMF0.0750.1500.3000.6001.182.364.759.512.519.0 20 40 80 d

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80 ) 020406080100Sieve Size (mm)^0.45Percent Passing JMF Blend0.0750.1500.3000.6001.182.364.759.512.519.025.0 Figure A-2: Gradation Chart for JMF and Blend of Project No. 2. (12.5mm Nominal size

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020406080100Sieve Size (mm)Percent Passing Blend JMF0.0750.1500.3000.6001.182.364.759.512.519.025.0 Figure A-3: Gradation Chart for JMF and Blend of Project No. 3. (12.5mm Nominal size) 81

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82 Figure A-4: Gradation Chart for JMF and Blend of Project No. 5. (9.5mm Nominal size) 020406080100Sieve Size (mm)^0.45Percent Passing Blend JMF0.0750.1500.3000.6001.182.364.759.512.519.025.0

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83 ) 020406080100Sieve Size (mm)^0.45Percent Passing JMF Blend 0.0750.1500.3000.6001.182.364.759.512.519.025.0 Figure A-5: Gradation Chart for JMF and Blend of Project No. 7. (12.5mm Nominal size

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020406080100Sieve Size (mm)^0.45Percent Passing JMF0.0750.1500.3000.6001.182.364.759.512.519.025.0 84 Figure A-6: Gradation Chart for JMF of Project No. 8. (12.5mm Nominal size)

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85 Table A-8: Cumulative Batch Weight for Project #1 BATCH WEIGHT, 4500g (SERVOPAC, Pine, APA) Gradation Batch Weight (g) 4500 #89 Stone W-10 Gra M-10 Gra #89 Stone W-10 Gra M-10 Gra Sieve Size Sieve, mm 50% 18.7% 31.3% 3/4" 19.0 100 100 100 0 2250 3092 1/2" 12.5 100 100 100 0 2250 3092 3/8" 9.5 100 100 100 0 2250 3092 #4 4.75 32 96 99 1530 2284 3106 #8 2.36 2 73 82 2205 2477 3345 #16 1.18 1 47 60 2228 2696 3655 #30 0.600 1 29 45 2228 2847 3866 #50 0.300 1 15 33 2228 2965 4035 #100 0.150 1 6 24 2228 3041 4162 #200 0.075 0.4 2.7 16.3 2241 3069 4270 Pan 0 0 0 0 2250 3092 4500 BATCH WEIGHT, 1100g (GTM) Gradation Batch Weight (g) (g) 1100 #89 Stone W-10 Gra M-10 Gra #89 Stone W-10 Gra M-10 Gra Sieve Size Sieve, mm 50% 18.7% 31.3% 3/4" 19.0 100 100 100 0 550 756 1/2" 12.5 100 100 100 0 550 756 3/8" 9.5 100 100 100 0 550 756 #4 4.75 32 96 99 374 558 759 #8 2.36 2 73 82 539 606 818 #16 1.18 1 47 60 545 659 893 #30 0.600 1 29 45 545 696 945 #50 0.300 1 15 33 545 725 986 #100 0.150 1 6 24 545 743 1017 #200 0.075 0.4 2.7 16.3 548 750 1044 Pan 0 0 0 0 550 756 1100 BATCH WEIGHT, 1500g (RICE DENSITY) Gradation Batch Weight 1500 #89 Stone W-10 Gra M-10 Gra #89 Stone W-10 Gra M-10 Gra Sieve Size Sieve, mm 50% 18.7% 31.3% 3/4" 19.0 100 100 100 0 750 1031 1/2" 12.5 100 100 100 0 750 1031 3/8" 9.5 100 100 100 0 750 1031 #4 4.75 32 96 99 510 761 1035 #8 2.36 2 73 82 735 826 1115 #16 1.18 1 47 60 743 899 1218 #30 0.600 1 29 45 743 949 1289 #50 0.300 1 15 33 743 988 1345 #100 0.150 1 6 24 743 1014 1387 #200 0.075 0.4 2.7 16.3 747 1023 1423 Pan 0 0 0 0 750 1031 1500

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86 Table A-9: Cumulative Batch Weight for Project #2 BATCH WEIGHT, 4500g (SERVOPAC, Pine, APA) Gradation Batch Weight (g ) 4500 #7 Stocrnr 2 89 S0 Scc 2 Stone #89 ne W-10 S 1 W-10 Sc #7 Stone # tone W-1 1 W-10 S Sieve Size S20.2%47.9% .2% % ieve, mm 21 10.7 3/4" 1100 100 100 00 0 909 3065 19 9.0 1 40 1/2" 190 100 100 00 91 909 3065 19 2.5 1 40 3/8" 948 99 100 00 473 931 3065 19 .5 1 40 #4 43 29 98 00 24393084 19 .75 1 882 40 #8 22 3 73 00 30003322 19 .36 1 891 40 #16 12 2 47 00 30213570 19 .18 1 891 40 #30 02 2 30 64 30213732 92 .600 891 41 #50 01 2 18 38 30213847 17 .300 900 43 #100 01 2 9 19 30213933 09 .150 900 44 #200 01 1 4 30433980 57 .075 9 900 44 Pan 00 0 0 0 30654019 00 909 45 BATCH WEIGHT, 1100g (GTM) Gradation Batch Weight (g ) 1100 #7 Stocrnr 2 89 S Scr 2 Stone #89 ne W-10 S 1 W-10 Sc #7 Stone # tone W-10 r 1 W-10 Sc Sieve Size S20.2%47.9% .2% % ieve, mm 21 10.7 3/4" 1100 100 100 00 22 222 749 9.0 1 982 1/2" 190 100 100 00 116 222 749 2.5 1 982 3/8" 948 99 100 00 216 227 749 .5 1 982 #4 43 29 98 00 754 .75 1 218 596 982 #8 22 3 73 00 812 .36 1 218 733 982 #16 12 2 47 00 873 .18 1 218 739 982 #30 02 2 30 64 912 25 .600 220 739 10 #50 01 2 18 38 940 55 .300 220 739 10 #100 01 2 9 19 961 78 .150 220 739 10 #200 01 1 4 973 89 .075 9 220 744 10 Pan 00 0 0 0 982 00 222 749 11 BATCH WEIGHT, 1500g (RICE DENSITY) Gradation Batch Weight (g ) 1500 #7 Stocrnc 2 89 S Scc 2 Stone #89 ne W-10 S 1 W-10 S #7 Stone # tone W-10 1 W-10 S Sieve Size S20.2%47.9%.2% % ieve, mm 21 10.7 3/4" 1100 100 100 00 0 303 1022 40 9.0 1 13 1/2" 190 100 100 00 30 303 1022 40 2.5 1 13 3/8" 948 99 100 00 158 310 1022 40 .5 1 13 #4 43 29 98 00 1028 40 .75 1 294 813 13 #8 22 3 73 00 1107 40 .36 1 297 1000 13 #16 12 2 47 00 1190 40 .18 1 297 1007 13 #30 02 2 30 64 1244 97 .600 297 1007 13 #50 01 2 18 38 1282 39 .300 300 1007 14 #100 01 2 9 19 1311 70 .150 300 1007 14 #200 01 1 4 1327 86 .075 9 300 1014 14 Pan 00 0 0 0 303 10221340 00 15

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87 Table A-10: Cumulative Batch Weight for Project #3 B ATCH WEIGHT, 4500g (SERVOPAC, Pine, APA) n Gradatio Batch Weight (g) 450 0 St S-1-A tone S1-B Stone 200 Scrn S-1-A S one S-1-B Stone 20 0 Scrn Sieve Size Sieve, m m .2%33 19 .5% 47.3% 3/4" 19. 0 100 100 100 0 864 2372 1/2" 12. 5 60 10864 2372 0 100 346 3/8" 9. 5 40 108 864 2372 0 100 51 #4 6 652 13922478 4.75 95 81 #8 6 7 2 22663095 2.36 66 81 #16 6 5 2 22963542 1.18 45 81 #30 0 5 5 1 22963883 0.60 29 82 #50 0 4 4 9 23114074 0.30 20 82 #100 0 3 3 8 8 23264330 0.15 83 #200 5 3 3 4 8 23264415 0.07 83 Pan 0 0 0 0 4 23724500 86 ATCH WEIGHT, 1100g (GTM) n Gradatio Batch Weight (g) 110 0 St S-1-A tone S1-B Stone 200 Scrn S-1-A S one S-1-B Stone 20 0 Scrn Sieve Size Sieve, m m .2%33 19 .5% 47.3% 3/4" 19. 0 100 100 100 0 211 580 1/2" 12. 5 60 10211 580 0 100 84 3/8" 9. 5 40 107 211 580 0 100 12 #4 6 659 340 606 4.75 95 19 #8 6 7 9 554 757 2.36 66 19 #16 6 5 9 561 866 1.18 45 19 #30 0 5 5 1 561 949 0.60 29 20 #50 0 4 4 3 565 996 0.30 20 20 #100 0 3 3 8 5 569 1058 0.15 20 #200 5 3 3 4 5 569 1079 0.07 20 Pan 0 0 0 0 1.2 580 1100 21 ATCH WEIGHT, 1500g (RICE DENSITY) n Gradatio Batch Weight (g) 150 0 S-to S-1-A tone S 1-B Stone 200 Scrn S-1-A S ne S-1-B Stone 20 0 Scrn Sieve Size Sieve, m m .2%33 19 .5% 47.3% 3/4" 19. 0 100 100 100 0 288 791 1/2" 12. 5 60 10288 791 0 100 115 3/8" 9. 5 40 103 288 791 0 100 17 #4 6 651 464 826 4.75 95 27 #8 6 7 1 755 1032 2.36 66 27 #16 6 5 1 765 1181 1.18 45 27 #30 0 5 5 4 765 1294 0.60 29 27 #50 0 4 4 6 770 1358 0.30 20 27 #100 0 3 3 8 9 775 1443 0.15 27 #200 5 3 3 4 9 775 1472 0.07 27 Pan 0 0 0 0 8 791 1500 28 B B

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88 Table A-11: Cumulative Batch Weight for Project #5 BATCH WEIGHT, 4500g (SERVOPAC, Pine, APA) G radation Batch Weight (g) sph Scr Med. Asph Scr ize Sie 2.8% 0.8% 6.4% 3/4" 19.0 10100 100 0 2826 3762 0 1/2" 12100 100 100 0 .5 2826 3762 3/8" 991 100 100 2 .5 54 2826 3762 #4 4.75 41 100 100 1 667 2826 3762 #8 2. 36 6 92 72 2 656 2901 3969 18 713 3079 4168 #50 0. 300 3 37 17 2 741 3416 4375 150 741 3622 4434 075 769 3715 4470 Pan 0 0 0 0 2 826 3762 4500 g (G tion Weigh d. Asph Scr W-10 Scrns 20.8% 16.4% 100 100 100 100 0 691 920 3/8" 9.5 91 100 1626 0 00 91 92 #4 4.41 100 1040 75 0 8 691 920 #8 2.6 92 72 6 36 49 709 970 #16 1.18 4 73 45 6 63 753 1019 63 801 1049 70 835 1069 70 885 1084 77 908 1093 Pan 0 0 0 0 69 0.8 920 1100 CE DENSITY) tion eigh 150 0 FC-3 StoMed. Asph r W-10 Scrns FC-3 Med. Scr Wrns ne Sc Stone Asph -10 Sc mm % 100 100 0 41 100 100 556 942 1254 #8 2.36 6 92 88967 1323 72 5 #16 1.4 73 45 90 18 4 1026 1389 #30 0.600 4 52 28 9 04 1092 1431 14 1139 1458 14 1207 1478 23 1238 1490 42 1254 1500 4500 FC-3 Stone Med. AW-10 Scrns FC-3 Stone W-10 Scrns Sieve Sve, mm 621 #16 1.4 73 45 2 #30 0.600 4 52 28 2713 3275 4293 #100 0.3 15 9 2 #200 0.2 5 4 2 BATCH WEIGHT, 1100TM) GradaBatcht (g) 1100 FC-3 Stone MeFC-3 Stone Med. Asph Scr W-10 Scrns Sieve Size Sieve, mm 62.8% 3/4" 19.0 100 100 0 691 920 1/2" 12.5 #30 0.600 4 52 28 6 #50 0.300 3 37 17 6 #100 0.150 3 15 9 6 #200 0.075 2 5 4 6 BATCH WEIGHT, 1500g (RI GradaBatch Wt (g) Sieve Size Sieve, 62.8% 20.8%16.4 3/4" 19.0 100 100 100 0 942 1254 1/2" 12.5 100 942 1254 3/8" 9.5 91 100 100 85 942 1254 #4 4.75 #50 0.300 3 37 17 9 #100 0.150 3 15 9 9 #200 0.075 2 5 4 9 Pan 0 0 0 0 9

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89 Table A-12: Cumulative Batch Weight for Project #7 BATCH WEIGHT, 4500g (SERVOPAC, Pine, APA) Gradation B atch Weight (g) 4500 one S-1-B Stone Asphs S-1-A Se Asphalt Scrns S-1-A St alt Scrn ton S-1-B Stone ieve, mm 24.5 12.5% .0% 3/4" 19.0 0 0 1103 1665 10 100 100 1/2" 12.5 4 1281103 1665 7 100 00 7 3/8" 9.5 4 7 100 584 1148 1665 92 #4 4.75 6 37 100 1036 1457 1665 #8 2.36 6 6 87 1036 1631 2034 #16 1.18 5 5 59 1047 1637 2827 #30 0.600 5 4 38 1047 1643 3423 #50 0.300 4 3 22 1058 1648 3876 #100 0.1 3 3.5 1665 BATCH WEIG HM) T, 1100g (GT radat eight (g 11 00 S-1-A Stone S-1-B Stone Asphalt Scrns S-1-A Se S-1-B SAsphals ton tone t Scrn ieve, 24. 12.5% .0% 3/4" 19.0 0 0 270 407 10 100 100 1/2" 12.5 74 100 100 70 270 407 3/8" 9.5 47 92 100 143 281 407 #4 4.75 6 100 253 356 407 37 #8 2.36 6 6 87 253 399 497 #16 1.18 5 5 59 256 400 691 #30 0.6 3 22 259 403 3 3 3.5 261 403 1076 Pan 0 0 0 0 270 407 1100 (RICE radat eight (g 1 500 S-1-A Stone S-1-B Stone Asphalt Scrns S-1-A S-1-B SAspha Stone tone lt Scrns ieve, mm 24 12.5% .0% 3/4" 19.0 1 00 10 368 555 100 00 1/2" 12.5 74 100 100 96 368 555 3/8" 9.5 47 92 100 195 383 555 #4 4.75 6 100 345 486 555 37 #8 2.3 Sieve Size S % 63 50 4 3 8 1058 1648 4273 #200 0.075 3 1069 1648 4401 Pan 0 0 0 0 1103 4500 Gion Batch W) Sieve Size Smm 5% 63 00 5 4 38 256 402 837 #50 0.300 4 403 948 #100 0.150 4 3 8 259 1045 #200 0.075 BATCH WEIGHT, 1500gDENSITY) Gion Batch W) Sieve Size S .5% 63 6 6 6 87 345 544 678 #16 1.18 5 5 59 349 546 942 #30 0.600 5 4 38 349 548 1141 #50 0.300 4 3 22 353 549 1292 #100 0.150 4 3 8 353 549 1424 #200 0.075 3 3 3.5 356 549 1467 Pan 0 0 0 0 368 555 1500

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APPE NDIX B MIXE VOLUMRREAND GTM TEST RESULTS TU R ETRIC P OPERTIE S AND CH ARACTE ISTICS, S RVOPAC

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91 Table B-1: Mixture Volumetric Properties and Compaction Characteristics Mixture No. Requirement #1 #M1 #2 #3 #5 #7 9.5mm 12.5mm #8 6.0 .00 .68 4.7 .86 .41 6 1.2 51 49 382 598 Design %AC 4.7 5.5 5.5 4.9 8.4 6.8 6.9 6.9 Nini 13 13.74 14.13 13.17 10.13 14.58 14.35 12.96 14.23 Ndes 4.19 4.07 4.34 4.35 4.24 4.67 4.39 4.50 3.86 4.0 % Air viod Nmax 2.24 3.14 3.09 2.67 2.81 2.47 2.38 Nini 87 86.26 85.87 86.83 89.87 85.42 85.65 87.04 85.77 Ndes 95.81 95.93 95.66 95.65 95.76 95.33 95.61 95.50 96.14 % Gmm Nmax 97.76 96.86 96.91 97.37 97.19 97.53 97.62 Nini 22.05 24.00 23.86 22.67 21.54 23.58 23.66 23.43 23.27 Ndes 14.16 15.47 15.17 14.81 16.40 15.00 14.56 15.98 1415.0 14.0 % VMA Nmax 13.86 14.11 13.69 15.03 13.05 14.20 12 Effective VMA (@ 4% AV) 31.5 37.1 35.4 33.4 22.8 3 Nini 41.05 42.74 40.77 41.90 52.23 38.18 38.39 44.67 38 Ndes 70.4 73.73 71.42 70.62 74.10 68.20 69.82 71.85 728(T4)/65-75(T5) 5-7 % VFA Nmax 83.87 77.77 77.42 82.20 78.49 82.58 8 % AC absorption 0.47 0.63 0.91 0.43 2.70 2.29 2.32 1.68 1. Effective %AC 4.23 4.87 4.59 4.47 5.7 4.51 4.58 5.22 4. Gmm 2.53 2.509 2.525 2.523 2.216 2.323 2.321 2.334 2. Gse 2.724 2.736 2.756 2.725 2.475 2.555 2.556 2.573 2. Gsb 2.691 2.691 2.691 2.694 2.325 2.418 2.418 2.470 2.503 Effect. Film thickness (micrometers) 24.4 52.3 48.3 40.5 18.6 35.3 Dust/Effective AC ratio 1.2 1.2 1.2 0.6 0.6 0.66 0.66 0.64 1.0 0.6% 1.2% T4 = Traffic level 4, T5 = Traffic level 5

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92 Figure B-1: Gyratory Shear vs Number of Cycles for Servopac Compaction at 1.25 Degrees 0 0 No. Cycles 4004505005506501110000 of Gs ) 1 600 (kpa #1 #2 #7 #5 #3 #8 #M 1

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93 Figure B-2: Gyratory Shear vs Number of Cycles for Servopac Compaction at 2.5 Degrees 5005205405605806006206401101001000No. of Cycles Gs (kkpa) #1 #2 #7 #5 #3

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94 mm 7580859095100105110050100150200250No. of Cycles %Gmm #1 #2 #7 #5 #3 Figure B-3: Percent G vs Number of Cycles for Servopac Compaction at 2.5 degrees

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95 es 4504704905105305505705906106306500.05.010.015.020.025.0% Air Voids Gs proj#1 proj#2 proj#7 proj#5 proj#3 Figure B-4: Gyratory Shear vs Percent Air Voids for Servopac Compaction at 2.5 Degre

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96 Figure B-5: Percent Air Voids vs Number of Cycles for Servopac Compaction at 2.5 degress -416111621050100150200250No. of Cycles % Air Voids #1 #2 #7 #5 #3

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97 Fi 70.075.080.085.090.095.0100.0105.00100200300400500600700No. OF CYCLES% Gmm #1 #2 #7 #5 #3 #8 #M1 gure B-6: Percent Gmm vs Number of Cycles for Compaction in GTM

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98 GTM 0.05.010.015.020.025.030.00100200300400500600700No. OF CYCLES% Air Voids #1 #2 #7 #5 #3 #8 #M1 Figure B-7: Percent Air Voids vs Number of Cycles for Compaction in

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APPENDIX C FIELD DATA: FALLING WEIGHT DEFLECTOMETER AND RUT DEPTHS

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100 Figure C-2: FWD Measurements at 30 Locations for Project #2 050100150200250051015202530LocationModulus, ksi Subgrade Base Figure C-1: FWD Measurements at 30 Locations for Project #1 050100150200250051015202530LocationModulus, ksi Base Subgrade

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101 Figure C-3: FWD Measurements at 30 Locations for Project #3 050100150200250051015202530LocationModulus, ksi Base Subgrade Figure C-4: FWD Measurements at 30 Locations for Project #5 050100150200051015202530LocationModulus, ksi Base Subgrade 250

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102 050100150200250051015202530LocationModulus, ksi Base Subbase Subgrade Figure C-5: FWD Measurements at 30 Locations for Project #7 0.50 0.000.050.100.150.200.250.300.350.400.45051015202530LocationRut Depth, inches Oct-99 Dec-00 Figure C-6: Field Rut Depths Measured at 30 Locations on Project #1

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103 Figure C-7: Field Rut Depths Measured at 30 Locations on Proje ct #2 0.000.050.100.150.200.250.300.350.400.450.50051015202530LocationRut Depth, inches Nov-99 Dec-00 Figure C-8: Field Rut Depths Measured at 30 Locations on Project #3 0.000.050.100.150.200.250.300.350.400.450.50051015202530LocationRut Depth, inches Nov-99 Dec-00

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104 igure C-10: Field Rut Depths Measured at 30 Locations on Project #7 0.000.050.100.150.200.250.300.350.400.450.50051015202530LocationRut Depth, inches Nov-99 Figure C-9: Field Rut Depths Measured at 30 Locations on Project #5 0.000.050.100.150.200.250.300.350.400.450.50051015202530LocationRut Depth, inches May-00 F

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LIST OF REFERENCES 1. Huber, G.A., “Methods To Achieve Rut-Resistance Durable Pavements,” Synthesis of Highway Practice 274, Transportation Research Board, National Research Council, Washington D.C., 1999. 2. Mehta, Y., Roque, R., “Evaluation of the FWD Data for Determination of Layer Moduli of Pavements,” Submitted for Publication in ASCE Journal of Materials in Civil Engineering, 2001. 3. McGennis, R.B., Anderson, R.M., Kennedy, T.W., Solamanian, M., Background of Superpave Asphalt Mixture Design and Analysis , Report No. FHWA-SA-95-003, Federal Highway Administration, Washington, D.C., 1994. odels for Planning 4. Paterson, W.D.O., Road Deterioration and Maintenance Effects: M and Management , The Highway Design and Maintenance Standards Series, A world Bank Publication, The Johns Hopkins University Press, Baltimore and London, 1987. 5. Nukunya, B., Roque, R., Tia, M., Birgisson, B., “Evaluation of VMA and other Volumetric Properties as Criteria for the Design and Acceptance of Durable Superpave Mixtures,” Journal of Association of Asphalt Paving Technologists, 2001. 6. Superpave Mix Design Manual for New Construction and Overlays , Report SHRP-A-407, Strategic Highway Research Program, National Research Council. Washington, D.C. (1993). 7. Blankenship, P.B., Mahboub, K.C., Huber, G.A., “Rational Method for Laboratory Compaction of Hot-Mix Asphalt,” in Transportation Research Record 1454, Transportation Research Board, National Research Council, Washington, D.C., 1994,pp. 144-153. 8. Standard Specification for Performance Graded Asphalt Binder , AASHTO Designation, MP1-93, American Association of State Highway and Transportation Officials, Washington, D.C., June 1996. 9. Bouldin, M.G., Way, G., Rowe, G.M., “Designing Asphalt Pavements for Extreme search Board, National Research Council, Washington, D.C., 1994, pp. 1-16. 10. Superpave Level 1 Mix Design Climates,” Transportation Research Record 1436, Transportation Re , Superpave Series No. 2 (SP-2), The Asphalt Institute, Lexington, Kentucky, 1994. 105

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106 11. Harvey, J., Monismith, C.L., “Effects of laboratory Asphalt Concrete Specification Preparation Variables on Fatigue and Permanent Deformation,” Test Results Using Strategic Highway Research Program A-003a Proposed Testing Equipment, in Transportation Research Record 1417, Transportation Research Board, National Research Council, Washington, D.C., 1993 PP. 38-48. 12. Mallick, R.B., “Use of Superpave Gyratory Compactor To Characterize Hot-Mix 3..B., “Effect of Mix Gradation on Rutting Potential of tion 4. .C., Button, J.W., Little, D.N., “Effect of Aggregate n 6. 7. 8. , T., MacKean, C., “Factors that Affect the Voids in Mineral Aggregate 19.tation Symposium, pp. 24-29, 2000. Asphalt,” Paper No. 99-1167, Transportation Research Record 1681, Transportation Research Board, National Research Council, Washington, D.C., 1999. Kandhal, P.S., Mallick, R 1 Graded Asphalt Mixtures,” Prepared for Presentation and Publication, TransportaResearch Board, National Research Council, Washington, D.C., 2001. Chowdhury, A., Grau, J.D 1 Gradation on Permanent Deformation of Superpave HMA,” Prepared for Presentatioand Publication, Transportation Research Board, National Research Council, Washington, D.C., 2001. 15. Kandhal, P.S., Cha kraborty, S., ”Evaluation of Voids in Mineral Aggregates for HMA Paving Mi xtures,” NCAT Report 96-4, 1996. Kandhal, P.S., Foo, K., Mallick, R.B.,”A Critical Review of VMA Requirement in 1 Superpave,” TRB Transportation Research Record No. 1609, National Research Council, pp. 21-27, 1998. Karakouzian, M., Dunning, R.I., Dunning, R.M., Stegeman, “Performance of Hot1 Mix Asphalt Using Coarse and Skip Graded Aggregates,” Journal o f Material in Civil Engineering, Vol. 8 Issue 2, pp. 101-107, 1996. Aschenbrener 1 in Hot-Mix Asphalt,” TRB, Transportation Research Record No. 1469, National Research Council, pp. 1-8, 1994. Hishop, W.P., Coree, B., “VMA as a Design Parameter in Hot-Mix Asphalt,” Continent Transpor 20. Hishop, W.P., Coree, B., A Laboratory Investigation into the Effects of AggregatesRelated Factors of Critical VMA in Paving Mixtures , Final Report No. TR-415. IowDepartment of Transportation, 2000. a 996. 21. Hinrichsen, J.A., Heggen, J., “Minimum Voids in Mineral Aggregates in Hot-Mix Asphalt Based on Gradation and Volumetric Properties,” TRB, Transportation Research Record 1545, National Research Council, pp. 75-79, 1

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107 22. Coree, B.J., Hishop, W., “Difficult Nature of Minimum Voids in Mineral AggregateHistorical Perspective,” TRB, Transportation Research Record No.1681, National Research Council, pp. 148-156, 1999. Elliot, R.P., Ford, M., Ghanim, M., Tu, F., “Effects of A s: 23.ggregate Gradation Variation on Asphalt Concrete Mix Properties,” TRB, Transportation Research Record No. 24.dations for Asphalt Mixtures Using Superpave,” TRB, Transportation Research Record No.1583, 25.ot Mix 1317, National Research Council, pp. 52-97, 1997. Anderson, R.M., Bahia, H., “Evaluation and Selection of Aggregate Gra National Research Council, pp. 91-97, 1997. Roberts, F.L., Kandhal, P.S., Brown, E.R., Lee, D.Y., Kennedy, T.W., H Asphalt Materials, Mixture Design and Construction , National Center for Asphalt . 26.ter avements Resistant to Rutting,” Transportation Research Record 1384, Transportation Research Board, National Research Council, 7. Cominsky, R.J., Huber, G.A., Kennedy, T.W., Anderson, R.M., The Superpave Mix Technology, NAPA Research and Education Foundation, Second Edition, 1996 Brosseaud, Y., Delorme, J.L., Hiernaux, R., “Use of LPC Wheel-Tracking RutTester to Select Asphalt P Washington, D.C., 1993, pp. 59-68. 2 Design Manual for New Construction and Overlays , Report SHRP-A-407, StrategicHighway Research Program, National Research Council, Washington, D.C., 1994253 pp. , ith ual Meeting of the Transportation Research Board, Washington, D.C., January, 2002. 29.pecification,” Proc., Association of Asphalt Pavement Technologists, Vol. 69, 2000. 30.ulation of Field Compaction of Asphalt Concrete,” Proc., Association of Asphalt Pavement Technologists, Vol. 31. Bushing, H.W., Goetz, W.H., “Use of Gyratory Testing Machine in Evaluating Bituminous Mixtures,” Highway Research Record No. 51, National Research 28. Birgisson, B., Darku, D.D., Roque, R., “Use of Superpave Gyratory Compactors wGyratory Shear Measurements for Evaluating the Rutting Performance of Mixes,” A Paper Submitted for Presentation and Publication at the Ann Corte, J.F., Serfass, J.P., “The French Approach to Asphalt Mixture Design: A Performance-Related System of S Ruth, B.E., Schaub, J.H., “Gyratory Testing Machine Sim 35, 1996, pp. 451-480. Council, Washington, D.C., 1964, pp. 19-43.

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108 32. Sigurjonsson, S., Ruth, B.E., “The Use of Gyratory Testing Machine to Evaluate Shear Resistance of Asphalt Paving Mixtures,” Transportation Research Record 1259, Transportation Research Board, N ational Research Council, Washington, D.C., 1990, pp. 63-75. 33.ord 1630, Transportation Research Board, National Research Council, Washington, D.C., 1998, pp. 89-97. 34.il, Washington, D.C., 1999. s,” 6. Hanson, I.D., Evaluation of Servopac Superpave Gyratory Compactor Butcher, M., “Determining Gyratory Compaction Characteristics Using Servopac Gyratory Compactor,” Transportation Research Rec Kandhal, P.S., Mallick, R.B., “Evaluation of Asphalt Pavement Analyzer for HMA Mix Design,” TRB, National Research Counc 35. Mehta, Y., Lopp, G., Roque, R., “Comprehensive Superpave Monitorin g ProjectUniversity of Florida, Report, 1999. 3 , Report of 37. of nt Height Test to Predict Rutting Potential of Mixes: Performance of Three Pavement Sections in North Carolina,” Transportation 38. Anderson, R.M., Bukowski, J.R., Turner, P.A., “Using Superpave Performance Tests to Evaluate Asphalt Mixtures,” Transportation Research Record 1681, Transportation 39. lt Concrete,” Proceedings of a Symposium, Effects of Aggregates and Mineral Fillers on Asphalt ing 0. Ruth, B.E., Tia, M., “Factors Influencing and Methodology for the Design and 1. Emery, J., “Asphalt Pavement Rutting Experience in Canada,” Proceedings of the 0, 2. Testa, DM., “Rutting –How Serious is the Problem?” Proceedings, Seventy-Four Annual Meeting of the American Association of State Highway and Transportation Officials in Wichita, Kansas, December 5-6, 1988, pp. 39-44. National Center for Asphalt Technology, Auburn, Alabama, 1998, pp. 1-16. Akhtarhusein, A.T., Khosla, N.P., Malpass, G.A., Waller, F.H., “EvaluationSuperpave Repeated Shear at Consta Research Record 1681, Transportation Research Board, Nationa l Research Council, Washington, D.C., 1999. No. 99-0522. Research Board, National Research Council, Washington, D.C., 1999. No. 99-0842. Ruth, B.E., Shen, X., Wang, L.H., “Gyratory Evaluation of Aggregate Blends toDetermine their Effect on Shear Resistance and Sensitivity to Aspha Mixture Performance, ASTM Publication STP 1147, American Society for Testand Materials, 1992, pp. 252-264. 4 Control of Asphalt Mixtures,” Proceedings of the Thirty-Ninth Annual Conference of Canadian Technical Asphalt Association, 1994, pp. 304-320. 4 Thirty-Fifth Annual Conference of Canadian Technical Asphalt Association, 199pp. 81-91. 4

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109 43. Stuart, K.D., Izzo, R.P., “Correlation of Superpave G*/Sin with Rutting Susceptibfrom laboratory Mixture Tests,” Transportation Research Record 1492, Transportation Research Board, National Research Council, Washington, D.C., 1995, pp. 176-183. ility 44. Moseley, H.L., An Evaluation of Superpave Compaction and Asphalt Mixture Properties , A Master’s Thesis Presented to the Graduate School of the UniversFlorida, 1999. ity of s 45. Kestory, E., Evaluation of Parameters to Determine the Suitability of Fine Aggregate for Use in Superpave Mixtures , A Master’s Thesis Presented to the Gradua te School of the University of Florida, 2000. 46.n of the Effects of Ground Tire Rubber (GTR) Twumasi, F.K., Laboratory Evaluatio on Rutting and Cracking Performance of Superpave Mixes , A Master’s Thesis 7. Buchanan, M.S., Brown, E.R., “Effect of Superpave Gyratory Compactor Type on on, 48. Hand, A.J., Stiady, J., White, T.D., Noureldin, A.S., Galal, K.A., “Gradation Effects on Hot-Mix Asphalt Performance,” Prepared for Presentation and Publication, 49.on Hot-Mix Asphalt Performance,” Prepared for Presentation and Publication, 01. 50.STM Publication STP 1147, American Society for Testing and Materials, 1992, pp. 211-224. 51. A Paper Submitted for Presentation and Publication at the Annual Meeting of the Transportation Research Presented to th e Graduate School of the University of Florida, 2001. 4 Compacted Hot Mix Asphalt (HMA) Density,” Prepared for Presentation and Publication, Transportation Research Board, National Research Council, WashingtD.C., 2001. Transportation Research Board, National Research Council, Washington, D.C., 2001. Hand, A.J., Epps, A.L., “Impact of Gradation Relative to Superpave Restricted Zone Transportation Research Board, National Research Council, Washington, D.C., 20 Fwa, T.F., Tan, S.A., “Laboratory Evaluation of Rutting Potential of Asphalt Mixtures,” Proceedings of a Symposium, Effects of Aggregates and Mineral Fillers on Asphalt Mixture Performance, A Mehta, Y., Asiamah, S., Lopp, G., Scholar, G., Tia, M., Roque, R., “Evaluation of Field Rutting Performance of Superpave Mixtures in Florida,” Board, Washington, D.C., January, 2002.

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BIOGRAPHICAL SKETCH Sylvester A . Asiamah was born in Kwahu Tafo, Ghana, on the 23rd of May 1970. epool at Pepease-Kwahu in Ghana six years later. In hy he obtained matpurDisemp e n he moved to the United States of andAfter completing the master’s program, Sylvester intends to go back into the practice of civil engineering and make meaningful contributions to society. He ahool at Nkawkaw, Ghana, in 1975 and proceeded to ease Catholic Junior Secondary Sch ttended St. Francis Primary Sc P the a program of study isical sciences at Suhum Secondary Technical School in Ghana where year 1984, he graduated from Junior Secondary and begun n p certificates for completing and successfully passing the physics, chemistry and hematics coursework in 1989. The year 1990 saw Sylvester enter the University of Science and Technology to sue a program in civil engineering, which he completed and was awarded a Bachelor of Science degree in Civil Engineering in March 1995. He then worked with the Ga trict Assembly’s Works Department in Accra, Ghana, as National Service Personnel in the capacity of Assistant Engineer for ten months and in September 1995 was loyed to work as Civil Engineer with Wacon Consulting Engineers in Accra, Ghana.remained at this post until December 1999 whe H America to begin a Master of Engineering program at the University of Florida’s Civil Coastal Engineering Department. 110