HMA Pavement Performance and Durability - Purdue e-Pubs

Final Report FHWA/IN/JTRP-2005/14 HMA PAVEMENT PERFORMANCE AND DURABILITY by Eliana del Pilar Vivar Graduate Research Assistant and John E Haddock Professor School of Civil Engineering Purdue University Joint Transportation Research Program Project Number: C-36-31N File No: 2-11-14 SPR-2646 Conducted in Cooperation with the Indiana Department of Transportation And the U.S Department of Transportation Federal Highway Administration The content of this report reflect the views of the authors who are responsible for the facts and accuracy of the data presented herein The contents not necessarily reflect the official views or policies of the Indiana Department of Transportation or the Federal Highway Administration at the time of publication This report does not constitute a standard, specification, or regulation Purdue University West Lafayette, IN 47907 April 2006 TECHNICAL REPORT STANDARD TITLE PAGE Report No Government Accession No Recipient's Catalog No FHWA/IN/JTRP-2005/14 Title and Subtitle HMA Pavement Performance and Durability Report Date April 2006 Performing Organization Code Author(s) Performing Organization Report No Eliana del Pilar Vivar and John E Haddock FHWA/IN/JTRP-2005/14 10 Work Unit No Performing Organization Name and Address Joint Transportation Research Program 1284 Civil Engineering Building Purdue University West Lafayette, IN 47907-1284 11 Contract or Grant No SPR-2646 13 Type of Report and Period Covered 12 Sponsoring Agency Name and Address Indiana Department of Transportation State Office Building 100 North Senate Avenue Indianapolis, IN 46204 Final Report 14 Sponsoring Agency Code 15 Supplementary Notes Prepared in cooperation with the Indiana Department of Transportation and Federal Highway Administration 16 Abstract It has long been argued that at densities higher than approximately 92 percent (air void contents lower than percent), a hotmix asphalt mixture is impermeable to water However, as densities become lower (air void contents higher) than this, small decreases in the density can yield exponential increases in permeability The objectives of this study were to better understand the increases in hot-mix asphalt pavement performance and durability that can be gained by increasing the initial pavement density and to better quantify the inter-relationship among pavement density, permeability, and moisture-induced damage The long-term performance and durability of four hot-mix asphalt mixtures at four different air void contents were evaluated with the dynamic modulus and beam fatigue apparatus The mixtures differed in both aggregate size and gradation In order to evaluate durability effects, performance tests were performed on unconditioned, moisture conditioned and ovenaged samples The results indicate that density (air void content) is a significant factor in the performance and durability of hotmix asphalt mixtures Its effects vary with aggregate size and gradation, but increases in mixture density (reductions in air voids content) produce improvements in the dynamic modulus (reduction of rutting potential) and fatigue life of a mixture Further, the fatigue life appears to be less sensitive to density (air voids content) than to moisture damage 17 Key Words 18 Distribution Statement HMA durability, HMA performance, porosity, permeability No restrictions This document is available to the public through the National Technical Information Service, Springfield, VA 22161 19 Security Classif (of this report) Unclassified Form DOT F 1700.7 (8-69) 20 Security Classif (of this page) Unclassified 21 No of Pages 181 22 Price iii TABLE OF CONTENTS Page LIST OF TABLES… …………………………………………………… vii LIST OF FIGURES …………………………………………………… x LIST OF SYMBOLS ………………………………………………… xvi CHAPTER INTRODUCTION……………………………………………… 1.1 Problem Statement……………………………………………… 1.2 Objectives and Scope of Study………………………………………… 1.3 Research Approach and Methodology……………………………… CHAPTER LITERATURE REVIEW………………………………………… 2.1 Permeability…….……………………………………… 2.1.1 Effect of Air Voids Content ……………………………………… 2.1.2 Effect of Aggregate Gradation and Size…… ………………… 2.1.3 Comparison of In-Service and Laboratory Results…………… 2.2 Moisture Susceptibility… …………………………………………… 2.2.1 Causes of Stripping … ………………………………… 11 2.2.2 Laboratory Testing… ………………………………………… 12 2.2.2.1 Conventional Test Method….……………………………… 12 2.2.2.2 PurWheel….………………………………… 13 2.2.3 Effect of Aggregate Gradation ……………………….………… 14 2.2.4 Comparison of In-Service and Laboratory Results …… … 15 2.3 Long-Term Performance and Durability…… ……………………… 15 iv Page 2.3.1 Permanent Deformation … ………………………………… 16 2.3.1.1 Causes… ……………………………………………… 17 2.3.1.2 Effect of Air voids…… ……………………………… 17 2.3.1.3 Effect of Aggregates………… ……… ………………… 18 2.3.1.4 Comparison of In-Service and Laboratory Results……… 19 2.3.2 Fatigue…… .……………………………………………… 19 2.3.2.1 Causes……………………………………… ………… 20 2.3.2.2 Effect of Air Voids Content.……………………………… 20 2.3.2.3 Effect of Aggregates………… … ……………………… 20 2.3.2.4 Effect of Conditioning………… .……………………… 21 2.3.2.5 Comparison of In-Service and Laboratory Results……… 21 CHAPTER EXPERIMENTAL METHODS………………….…….… 22 3.1 Experimental Design…….…………………………………………… 22 3.1.1 Plan of Study… ………………………………………………… 22 3.1.2 Test Methods…………………… ……………………… 23 3.2 Materials…… … ……………………………………………………… 23 3.2.1 Binder…………….………………………………………………… 23 3.1.2 Aggregates……….…………………… ……………………… 24 3.3 Mixture Designs….……………………………………………………… 24 3.4 Analysis Procedures……………………………………………………… 25 3.4.1 Analysis of Variance……………………………………………… 25 3.4.2 Tukey Multiple Comparison Procedure………………………… 26 CHAPTER PERMEABILITY………… ………………………………… 27 4.1 Falling Head Permeability.……………………………………………… 27 4.1.1 Background………… .………………………………………… 27 4.1.2 Testing Procedures and Parameters……… ………………… 28 v Page 4.1.3 Results………… …………………………………………… 29 4.2 CoreLok………… …………………………………… 33 4.2.1 Background………… …………………………………………… 35 4.2.2 Testing Procedures and Parameters……… ……………… 35 4.2.3 Results…………… …………………………………… 37 4.3 Statistical Analysis of Results……………………………………… 40 4.3.1 Permeability………………………………………………………… 40 4.3.2 Porosity…………………………………………………………… 43 CHAPTER MOISTURE SUSCEPTIBILITY……………………………… 45 5.1 AASHTO T283… …………………………………………………… 45 5.1.1 Background…… ………………………………………………… 45 5.1.2 Specimen Preparation…………………………………………… 45 5.1.3 Testing Procedures………… .……………………………… 46 5.1.4 Results……… .…………………………………………… 47 5.2 PurWheel… ……………………………………………………… 48 5.2.1 Background…… ………………………………………………… 48 5.2.2 Specimen Preparation ………………………………………… 49 5.2.3 Testing Procedures and Parameters…… …………………… 50 5.2.4 Results……… ……………………………………………… 51 CHAPTER PERMANENT DEFORMATION………… …………………… 55 6.1 Background……… ………………………………………………… 55 6.2 Specimen Preparation………………… …………………………… 57 6.3 Testing Procedures and Parameters……… ……………………… 58 6.4 Results… ……………………………………………………… 59 6.4.1 Dynamic Modulus … … ……………………………………… 59 6.4.2 Phase Angle…… .…………………………………………… 62 vi Page 6.3 Statistical Analysis of Results……………………………………… 67 CHAPTER FATIGUE TESTING…………………………………………… 77 7.1 Background……… ………………………………………………… 77 7.2 Specimen Preparation… …………………………………………… 78 7.3 Testing Procedures and Test Parameters …………………………… 80 7.4 Results…….……………………………………………………… 81 7.4.1 Initial Flexural Stiffness………………………… ……………… 81 7.4.2 Cycles to failure ….… ………………………………………… 84 7.5 Statistical Analysis of Results……………………………………… 87 7.5.1 Initial Flexural Stiffness… ……………………………………… 87 7.5.2 Cycles to Failure… ……………………………………………… 90 CHAPTER CONCLUSIONS AND RECOMMENDATIONS……………… 93 8.1 Summary………………………………………………………… 93 8.2 Conclusions…………………………………… ……………………… 94 8.3 Recommendations……………………………………………………… 96 8.4 Implementation…………………………………………………………… 97 LIST OF REFERENCES……………………………………………………… 98 APPENDICES Appendix A……………………………………………………………… 104 Appendix B……………………………………………………………… 110 Appendix C……………………………………………………………… 114 Appendix D……………………………………………………………… 175 vii LIST OF TABLES Table Page Table 3.1 Experimental Design 22 Table 3.2 Mixture Design Summary 25 Table 4.1 Permeability Results 31 Table 4.2 Bulk Specific Gravity, Porosity and Absorption Results 38 Table 4.3 Permeability ANOVA Results… …….………… 40 Table 4.4 Tukey Groups (Permeability) …………………… 41 Table 4.5 Permeability Regression Results……………………… 42 Table 4.6 Porosity ANOVA Results….……………………………………… 43 Table 4.7 Tukey Groups (Porosity) 44 Table 5.1 Moisture Susceptibility Test Results 48 Table 5.2 PurWheel Test Results… 52 Table 6.1 Dynamic Modulus Testing Parameters… ……………… … 58 Table 6.2 Dynamic Modulus Test Conditions…………………… … 59 Table 6.3 Tukey Group of Factors for Dynamic Modulus……… 68 Table 6.4 Tukey Group of Factors for Phase Angle (20C) 69 Table 6.5 Tukey Group of Factors for Phase Angle (40C) 69 Table 6.6 Tukey Groups for Difference Between Unconditioned and Moisture Conditioned Dynamic Modulus 71 Table 7.1 Beam Fatigue Parameters ………………………… 80 Table 7.2 ANOVA Results for Initial Flexural Stiffness…………………… 87 Table 7.3 Tukey Groups (Initial Flexural Stiffness) …………………… 88 Table 7.4 ANOVA Results for Number of Cycles to Failure .………… 90 Table 7.5 Tukey Groups (Fatigue Life) ….…………………… 91 viii Appendix Table Page Table B.1 Mixture Superpave Design Mix Formula 110 Table B.2 Mixture Superpave Design Mix Formula 111 Table B.3 Mixture Superpave Design Mix Formula 112 Table B.4 Mixture Superpave Design Mix Formula 113 Table C.1 Mixture Unconditioned Dynamic Modulus (20C) 114 Table C.2 Mixture Moisture Conditioned Dynamic Modulus (20C)… 115 Table C.3 Mixture Unconditioned Dynamic Modulus (40C) 116 Table C.4 Mixture Moisture Conditioned Dynamic Modulus (40C) 117 Table C.5 Mixture Unconditioned Dynamic Modulus (20C) 118 Table C.6 Mixture Moisture Conditioned Dynamic Modulus (20C) 119 Table C.7 Mixture Unconditioned Dynamic Modulus (40C) 120 Table C.8 Mixture Moisture Conditioned Dynamic Modulus (40C)… 121 Table C.9 Mixture Unconditioned Dynamic Modulus (20C)… 122 Table C.10 Mixture Moisture Conditioned Dynamic Modulus (20C) 123 Table C.11 Mixture Unconditioned Dynamic Modulus (40C) 124 Table C.12 Mixture Moisture Conditioned Dynamic Modulus (40C) 125 Table C.13 Mixture Unconditioned Dynamic Modulus (20C) 126 Table C.14 Mixture Moisture Conditioned Dynamic Modulus (20C) 127 Table C.15 Mixture Unconditioned Dynamic Modulus (40C) 128 Table C.16 Mixture Moisture Conditioned Dynamic Modulus (40C)… 129 Table C.17 Mixture Unconditioned Phase Angle (20C)…… 149 Table C.18 Mixture Moisture Conditioned Phase Angle (20C) 150 Table C.19 Mixture Unconditioned Phase Angle (40C)…… 151 Table C.20 Mixture Moisture Conditioned Phase Angle (40C) 152 Table C.21 Mixture Unconditioned Phase Angle (20C)…… 153 Table C.22 Mixture Moisture Conditioned Phase Angle (20C) 154 Table C.23 Mixture Unconditioned Phase Angle (40C)…… 155 Table C.24 Mixture Moisture Conditioned Phase Angle (40C) 156 ix Appendix Table Page Table C.25 Mixture Unconditioned Phase Angle (20C)…… 157 Table C.26 Mixture Moisture Conditioned Phase Angle (20C) 158 Table C.27 Mixture Unconditioned Phase Angle (40C)…… 159 Table C.28 Mixture Moisture Conditioned Phase Angle (40C) 160 Table C.29 Mixture Unconditioned Phase Angle (20C)…… 161 Table C.30 Mixture Moisture Conditioned Phase Angle (20C) 162 Table C.31 Mixture Unconditioned Phase Angle (40C)…… 163 Table C.32 Mixture Moisture Conditioned Phase Angle (40C) 164 Table D.1 Mixture Beam Fatigue Results ………………………… … 175 Table D.2 Mixture Beam Fatigue Results ………………………… … 176 Table D.3 Mixture Beam Fatigue Results ………………………… … 177 Table D.4 Mixture Beam Fatigue Results ………………………… … 178 x LIST OF FIGURES Figure Page Figure 2.1 Cohesive and Adhesive failures (after [21])…………… 10 Figure 2.2 Wheel Tracking Results (after [25]) 14 Figure 2.3 Stages of Permanent Deformation (after [1]) 17 Figure 4.1 Falling Head Permeameter 28 Figure 4.2 Permeability Results…… 30 Figure 4.3 Mixture Permeability………………… 32 Figure 4.4 Mixture Permeability………………… 32 Figure 4.5 Mixture Permeability………………… 33 Figure 4.6 Mixture Permeability………………… 33 Figure 4.7 Comparison of CoreLok and AASHTO T166 37 Figure 4.8 CoreLok Porosity and Air Voids… … 39 Figure 4.9 CoreLok Porosity and AASHTO T166 Air Voids…….…………… 39 Figure 5.1 Indirect Tensile Strength Equipment 46 Figure 5.2 AASHTO T283 Conditioned Samples 48 Figure 5.3 Linear Compactor…………………………………………………… 49 Figure 5.4 PurWheel… 50 Figure 5.5 PurWheel Samples after Testing 51 Figure 5.6 Mixture (9.5-mm NMAS, Coarse-graded) PurWheel Results… 53 Figure 5.7 Mixture (9.5-mm NMAS, Fine-graded) PurWheel Results…… 53 Figure 5.8 Mixture (19.0-mm NMAS, Coarse-graded) PurWheel Results 54 Figure 5.9 Mixture (19.0-mm NMAS, Fine-graded) PurWheel Results 54 Figure 6.1 Stress and Strain in the Dynamic Modulus Test…… ………… 56 Figure 6.2 Dynamic Modulus Sample ………….……………………………… 57 Phase Angle (Mixture 40C Unconditioned) - - Air voids (%) FIGURE C.51 Mixture Unconditioned Phase Angle (40C) Phase Angle (Mixture 40C Moisture Conditioned) - 17.0 15.0 2.00 - - - I I I I i 4.00 6.00 8.00 10.00 12.00 Air voids (%) FIGURE C.52 Mixture Moisture Conditioned Phase Angle (40C) - - - - Phase Angle (Mixture 20C Unconditioned) - - Air voids (%) FIGURE C.53 Mixture Unconditioned Phase Angle (20C) Phase Angle (Mixture 20C Moisture Conditioned) - 2.00 4.00 - 6.00 8.00 10.00 12.00 Air voids (%) FIGURE C.54 Mixture Moisture Conditioned Phase Angle (20C) Phase Angle (Mixture 40C Unconditioned) - - 31 O -p 25.0 23.0 - - U) n - -A ~ ~ ! 21.0 19.0 17.0 4) p p - - i 15.0 2.00 4.00 I p~ 6.00 8.00 10.00 12.00 Air voids (%) FIGURE C.55 Mixture Unconditioned Phase Angle (40C) Phase Angle (Mixture 40C Moisture Conditioned) - 17.0 - 15.0 2.00 - - - - 4.00 6.00 Air voids 8.00 10.00 i - - 12.00 (YO) FIGURE C.56 Mixture Moisture Conditioned Phase Angle (40C) Phase Angle (Mixture 20C Unconditioned) - 2.00 4.00 - 6.00 8.00 10.00 12.00 Air voids (%) FIGURE C.57 Mixture Unconditioned Phase Angle (20C) Phase Angle (Mixture 20C Moisture Conditioned) - - Air voids (Oh) FIGURE C.58 Mixture Moisture Conditioned Phase Angle (20C) Phase Angle (Mixture 40C Unconditioned) - 00 00 - 00 8.00 10.00 12.00 Air voids (%) FIGURE C.59 Mixture Unconditioned Phase Angle (40C) Phase Angle (Mixture 40C Moisture Conditioned) - - Air voids (YO) ! I FIGURE C.60 Mixture Moisture Conditioned Phase Angle (40C) - , , qj ,*L '' I/ ,, " ' , / I ' I1 , , ,/ : / *: ~~~ , :,, , ~~~ ~~~ ~~~~ :/j:l~ ;!I ; , , , ! d ,! , I:, , l , r cr, co d + (TI a, - m a3 r4 -0 C (TI b- (4 TABLE D.2 Mixture Beam Fatigue Results TABLE D.3 Mixture Beam Fatigue Results i Unconditionedsamples I I ! - Air voids ( O X ) 10 11 - I - - (a) - - I - - - Long-term aged samples 10 Air voids 1%) -1 + Mixture n Mixture A Mixture x Mixture - 11 Moisture conditioned samples 10 11 Air voids (%) ~ A Mixture x Mixture ~ -p. -. p -p.p - FIGURES D.l (a) Unconditioned, (b) Oven-Aged, and (c) Moisture Conditioned Initial Stiffness 2000 3000 4000 5000 6000 7000 8000 Stiffness - Unconditioned (MPa) - - Mixture Mixture r Mixture 3x ~ i x t i r e y - - (a) 6000 - - - - u al E -w0 e 5500 5000 -~ - 2000 3000 4000 5000 6000 7000 8000 - Stiffness Unconditioned (MPa) I - ~ M y x t u r e Mixture 2r Mixture 3x M~xture4 -' FIGURE D.2 Initial Flexural Stiffness Comparison of (a) Unconditioned and Oven-Aged; and (b) Unconditioned and Moisture Conditioned ... understand the increase in HMA pavement performance and durability that can be gained by increasing the initial pavement density; and Better quantify the inter-relationship among HMA pavement. .. understand the increases in hot-mix asphalt pavement performance and durability that can be gained by increasing the initial pavement density and to better quantify the inter-relationship among pavement. .. Approach and Methodology Pavement density is an important parameter that can influence the performance and durability of HMA, but it is unclear to what extent long-term performance and durability