EVALUATIONOFASPHALTADDITIVESFORIMPROVEDCRACKING ANDRUTTINGRESISTANCEOFASPHALTPAVINGMIXTURES By CHUANG-TSAIRSHIH ADISSERTATIONPRESENTEDTOTHEGRADUATESCHOOL OFTHEUNIVERSITYOFFLORIDAINPARTIALFULFILLMENT OFTHEREQUIREMENTSFORTHEDEGREEOF DOCTOROFPHILOSOPHY UNIVERSITYOFFLORIDA 1996 ACKNOWLEDGMENTS ItisveryfortunatefortheauthortohavehadDr.MangTiaasadvisorand chairmanofthesupervisorycommittee. Withouthissupport,guidanceandcontinuous encouragement,thisworkwouldnothavebeenpossible. SpecialthanksgotoDr.Byron E.Ruth,whohaskindlyservedasthecochairmanofhissupervisorycommittee,forhis technicaladviceandhumor. SincerethanksaregiventoDr.ReynaldoRoqueforhis detailedadvicethroughthechallengingstagesofthisstudy. Specialappreciationis expressedtoDr.DavidBloomquistforhispatientguidanceontheprojectssincetheearly stageofthestudy. ThanksaregiventoDr.MarkC.K.Yangforservingontheauthor’s supervisorycommitteeandhavinggivenofhisexpertiseandtime. ThanksareextendedtotheFloridaDepartmentofTransportation(FDOT)for providingfinancialsupport,andtotheFDOTpersonnel,particularlyT.Dillow,G.Lopp, G.Schiller,A.TurnerandP.Upshaw. TheauthorwouldliketothankE.Dobson,D. Richardson,andB.Studstill,andtoalltheotherstudentsandfriends,Shin-CheHuang, Chui-TeChiu,Ming-GinLee,Jua-RongChou,DaiLu,XiaofangWang,Tu-MingLeung, A.M.Agosta,W.Buttlar,T.Safer,S.QarghaandG.Jonnsonfortheirhelp. Finally,theauthorisdeeplyindebtedtohisparentsandsistersfortheirlove, encouragementandsupportthroughouthisstudies. 11 TABLEOFCONTENTS Page ACKNOWLEDGMENTS ii LISTOFTABLES vi LISTOFFIGURES ix ABSTRACT xiv CHAPTERS 1 INTRODUCTION 1 1.1Background 1 1.2StudyObjectives 2 2 LITERATUREREVIEW 3 2.1DistressesInAsphaltConcretePavements 3 2.2MechanismsofPrimaryPavementDistress 5 2.2.1MechanismofLowTemperatureCracking 5 2.2.2MechanismofThermalFatigueCracking 5 2.2.3MechanismofRutting 6 2.3FactorsContributingtoPavementDistress 7 2.3.1FactorsAffectingLowTemperatureCracking andThermalFatigueCracking 7 2.3.1.1 Material 8 2.3.1.2 Environment 8 2.3.1.3 PavementStructure 9 2.3.2 FactorsAffectingRutting 9 2.3.2.1 Aggregate 10 2.3.2.2 Binder 11 2.3.2.3 Mixture 11 2.3.2.4 Test/FieldConditions 13 2.4ImprovementofPavementPerformance byUsingtheModifiedBinders 14 iii 2.4.1 ClassificationofModifiers 14 2.4.2 EffectsofModifiersonAsphaltMixtures 18 2.4.2.1 Gilsonite 18 2.4.2.2 Thermoplastic 18 2.4.2.3 Elastomer 19 2.4.2.4 Thermoset 20 3 RESEARCHPROGRAMANDINSTRUMENTATION 21 3.1LaboratoryTestingProgramonAsphaltCements 22 3.1.1MaterialsTested 22 3.1.2BrookfieldRheometerTest 24 3.1.3CannonSchweyerConstantStressRheometer 27 3.1.4FraassBreakingPointTest 29 3.1.5SHRPBendingBeamRheometer 29 3.1.6SHRPDynamicShearRheometer 31 3.1.7SHRPDirectTensionTester 33 3.1.8InfraredSpectralAnalysis 36 3.2InvestigationonAgingofAsphaltCements 38 3.2.1MaterialsTested 38 3.2.2CaliforniaTiltOven 39 3.2.3PressureAgingVessel 39 3.3LaboratoryTestingProgramonAsphaltMixtures 42 3.3.1MaterialsTested 42 3.3.2DiametralResilientModulusTest 45 3.3.3IndirectTensileCreepTest 51 3.3.4IndirectTensileStrengthTest 54 3.3.5LoadedWheelTest 54 3.3.6AsphaltExtractionandRecoveryMethods 57 4 RESULTSOFBINDERSTESTS 58 4.1StatisticalModel 58 4.24E.f4f.e1ctsofModifiersontheHigh-TemperatureProperties 59 4.2.1BrookfieldViscosity 59 4.2.2ResultsofDynamicShearRheometerTest 66 4.3EffectsofModifiersontheIntermediate-TemperatureProperties76 4.3.1Penetration 26 4.3.2ResultsofDynamicShearRheometerTest 76 4.3.3ResultsofConstantStressRheometerTest 86 4.4EffectsofModifiersontheLow-TemperatureProperties 90 FraassBreakingPointTest 90 IV 4.4.2ResultsofBendingBeamRheometerTest 97 4.4.3ResultsofDirectTensionTest 104 4.5EffectsofModifiersonTemperatureSusceptibility 109 4.5.1PenetrationViscosityNumber 109 4.5.2BitumenTestDataChart(BTDC) 112 4.6EffectsofModifiersonAgingCharacteristics 124 4.6.1ViscosityAgingIndex 124 4.6.2CarbonylRatioIndex 128 4.7SummaryofFindings 128 5 RESULTSOFASPHALTMIXTURETESTS 135 5.1EffectsofModifiersonHighTemperatureCharacteristics .. 135 5.1.1ResultsofGyratoryTestingMachineTest 135 5.1.2ResultsofLoadedWheelTest 141 5.2EffectsofModifiersonLowTemperatureCharacteristics... 150 5.2.1ResultsofDiametralResilientModulusTest 150 5.2.2ResultsofIndirectTensileCreepTest 156 5.2.3ResultsofIndirectTensileStrengthTest 164 5.3ResultsofTestsonRecoveredAsphaltResidues 167 i 5.4RelationshipsBetweenBinderandMixtureProperties 172 5.5SummaryofFindings 175 6 CONCLUSIONSANDRECOMMENDATIONS 178 6.1Conclusions 178 6.2Recommendations 181 APPENDICES A RESULTSOFBINDERTESTS 182 B RESULTSOFMIXTURETESTS 212 REFERENCES 224 BIOGRAPHICALSKETCH 230 v LISTOFTABLES Tables Ease 2.1 PavementDistressandPossibleCausesinAsphaltConcretePavements 4 2.2 AsphaltAdditivesCurrentlyBeingUsedorTestedinPavements 16 2.3 ClassificationofPolymericMaterials 17 3.1 ListofModifiedAsphaltBindersTested 23 3.2 SourceofAggregatesandJobMixFormulaforDense-gradedMixes 24 4.1 ResultsofANOVAandDuncan’sGroupingontheBrookfieldViscosity , oftheOriginalandPAV-20hour-agedBinders 61 4.2 SummaryofResultsofRegressionAnalysesfortheRelationshipBetween BrookfieldViscosityandLevelofModifierAdded 64 4.3 ResultsofANOVAandDuncan’sGroupingontheComplexModulus at60°Cat10rad/secoftheOriginalandTFOT-163°C-agedBinders 67 4.4 SummaryofResultsofRegressionAnalysesfortheRelationship BetweenComplexModulusat60°CandLevelofModifierAdded 70 4.5 ResultsofANOVAandDuncan’sGroupingonthePhaseAngleat60°C at10rad/secoftheOriginalBindersandTFOT-163°C-agedBinders 72 4.6 SummaryofResultsofRegressionAnalysesontheRelationship BetweentheComplexModulusandTemperature 75 4.7 ResultsofANOVAandDuncan’sGroupingonthePenetration at25°CoftheOriginalBindersandPAV-20hour-agedBinders 77 4.8 ResultsofANOVAandDuncan’sGroupingofPAV-20hour-agedBinders onthebasisofComplexModulusat20°Cat10rad/sec 80 vi 4.9 ResultsofANOVAandDuncan’sGroupingofPAV-20hour-aged BindersonthebasisofPhaseAngleat20°Cat10rad/sec 82 4.10 SummaryofResultsofRegressionAnalysesRelatingtheComplexModulus at20°CtotheLevelofModifierAddedforPAV-20hour-agedBinders .... 84 4.11 SummaryofResultsofRegressionAnalysesforRelatingtheComplex Modulusat10rad/sectoTemperatureforPAV-20hour-agedBinders 87 4.12 ResultsofAN0VAandDuncan’sGroupingofPAV-20hour-aged BindersontheBasisofG*sin6at20°Cat10rad/sec 88 4.13 ResultsofANOVAandDuncan’sGroupingofPAV-40hour-aged Bindersat5°Cand25°ContheBasisofConstantPowerViscosity 91 4.14 ResultsofANOVAandDuncan’sGroupingofOriginalandCTO-72hour- agedBindersonthebasisofFraassBreakingPoint 94 4.15 ResultsofANOVAandDuncan’sGroupingontheCreepStiffnessof PAV-20hour-agedBindersat-12°Cand-24°C 98 i 4.16 SummaryofResultsofRegressionAnalysesfortheRelationshipBetween theCreepStiffnessat-12°CandtheLevelofModifierAdded 103 4.17 ResultsofANOVAandDuncan’sGroupingofPAV-20hour-aged BindersontheBasisofm-valueat-12°Cand-24°C 105 4.18 ResultsofANOVAandDuncan’sGroupingofPVN^.^)ofUnaged andPAV-20hour-agedBinders 110 4.19 CarbonylRatioIndexesofAsphaltBinders 129 A.l BrookfieldViscosityat60°C 182 A.2 G*at1.59Hz(10rad/sec) 184 A.3 PhaseAngleat1.59Hz 187 A.4 Penetrationat25°C 191 A.5 SchweyerConstantPowerViscosityat5°C 193 A.6 SchweyerConstantPowerViscosityat25°C 197 vii A.7 FraassBreakingPointTemperature 201 A.8 CreepStiffnessofPAV20HoursResidueat-12°Cand-24°C 203 A.9 Them-ValueofPAV20HoursResidueat-12°Cand-24°C 204 A.10 ResultsofDirectTensionTestat-12°ConPAV-20hour-aged AsphaltBinders 205 A.11 PenetrationViscosityNumber[PAV(25.60)] 206 A.12 BrookfieldViscosityAgingIndexat60°C 208 A.13 ResultsofInfararedSpectralAnalysis 210 B.l ResultsofGyratoryTestingMachine 212 B.2 ResultsofLoadedWheelTest 216 B.3 ResultsofDiametralResilientModulusTests 217 iB.4 ResultsofIndirectTensileCreepTests 221 B.5 ResultsofIndirectTensileStrengthTestat-10°C 222 B.6 ResultsofTestsonRecoveredBinders 223 Vlll LISTOFFIGURES Earn gage 3.1 FlowChartofActivitiesofSubtaskI 25 3.2 BrookfieldRheometerReadingandControllingSystem 26 3.3 CannonSchweyerRheometerSystem 28 3.4 FraassBreakingPointTester 30 3.5 BendingBeamRheometer 32 3.6 BohlinDynamicShearRheometerTestSystem 34 3.7 DirectTensionTester 35 3.8 TheFourierTransformationInfraredSpectrophotometer 37 3.9 FlowChartofActivitiesofSubtaskII 40 3.10 RollingThinFilmOven 41 3.11 PressureAgingVesselTestSystem 43 3.12 FlowChartofActivitiesofSubtaskIII 46 3.13 IndirectTensileTestingDevice 47 3.14 TypicalLoad,DeformationversusTimeRelationshipsina Repeated-LoadIndirectTensionTest 50 3.15 LoadedWheelTester 56 4.1 RelationshipBetweenBrookfieldViscosityat60°CandLevel ofGilsoniteAddedonUnagedAC-5 63 IX 0 4.2 RelationshipBetweenComplexModulusat60°Cat1 rad/sec andLevelofGilsoniteAddedonUnagedAC-5 go 4.3 RelationshipBetweenComplexModulusat10rad/secandTest TemperatureforUnagedGilsoniteModifiedAC-5Binders 74 4.4 ComparisonofPenetrationat25°CforUnagedandPAV-20hour- agedGroundTireRubberModifiedBinders 79 4.5 RelationshipBetweenComplexModulusat20°Cand10rad/secand LevelofGilsoniteAdditiontoPAV-20hour-agedAC-5 83 4.6 RelationshipBetweenComplexModulusat10rad/secandTest TemperatureonPAV-20hour-agedGTRModifiedAC-20Binders 85 4.7 PlotofG*sin6versusTemperatureforPAV-20hour-agedSBR ModifiedAC-20Binders g9 4.8 ComparisonofConstantPowerViscostiyat5°CforTFOT-185°C- agedUnmodifiedandModifiedAC-20Binders 93 4.9 ComparisonofFraassBreakingPointTemperaturesofUnagedand PAV-20hour-agedAC-20Binders 96 4.10 ComparisonofCreepStiffnessat-12°Cand-24°CforPAV-20hour- agedAC-20Binders jqo 4.11 RelationshipBetweenCreepStiffnessat-12°CandLevelofGTR AddedonPAV-20hour-agedAC-20 102 4.12 Comparisonofm-valueat-12°Cand-24°CforPAV-20hour- agedAC-20Binders 107 4.13 ComparisonofFailureStrainat-12°CforPAV-20hour-agedBinders ... 108 4.14 ComparisonofPenetrationViscosityNumberforUnagedand PAV-20hour-agedAC-20Binders 113 4.15 BitumenTestDataChartsforUnagedGilsoniteModifiedAC-5Binders .. 114 4.16 BitumenTestDataChartsforPAV-20hour-agedGilsonite ModifiedAC-5Binders H5 x