paved644

DD-6441of11WESTVIRGINIADEPARTMENTOFTRANSPORTATIONDIVISIONOFHIGHWAYSDESIGNDIRECTIVEDD–644ASPHALTPAVEMENTJuly1,2016AttachedistheWestVirginiaDepartmentofTransportation,DivisionofHighwayspolicyon"AsphaltPavement".
ThisDesignDirective(DD)providesguidanceonselectingasphaltpavementmixdesignmethodsandtypesofasphaltpavement.
Italsoprovidesdescriptionsofsituationsthatrequirepolymer-modifiedasphalts,andmethodsforcalculatingquantitiesandtypesofmaterialsthataretobeused.
AttachmentDD-6442of11ASPHALTPAVEMENTASPHALTSPECIFICATIONTYPESELECTIONSection410oftheStandardSpecifications,AsphaltBaseandWearingCourses,PercentWithinLimits(PWL)andtheappropriatepayitemswillbeusedonthefollowingtypeprojects:1.
NewConstructionofmultilanedividedhighwayswherethemainlinepavementisasphaltpavement.
2.
Overlayprojectsonexistingmultilanedividedhighways.
Section401and/or402andtheappropriatepayitemswillbeusedonallotherprojects.
TYPESOFASPHALTPAVEMENTSuperpaveAsphaltPavement:"Superpave"standsforSuperiorPerformingAsphaltPavements.
Itrepresentsanimprovedsystemforspecifyingthecomponentsofasphaltconcrete,asphaltmixturedesignandanalysis,andasphaltpavementperformanceprediction.
TheStrategicHighwayResearchProgram(SHRP)developedtheSuperpaveasphaltpavementmixdesignmethodintheearly1990's.
MarshallAsphaltPavement:BruceMarshalldevelopedthe"Marshall"methodofasphaltmixdesigninthelate1930'sfortheMississippiHighwayDepartment.
ThismethodhasbeenusedbytheWVDOTforatleastthepast40yearsandwasthestandardspecification.
ASPHALTPAVEMENTMIXDESIGNTYPESELECTIONSuperpaveasphaltpavementistobeusedforthefollowingtypeprojects:1.
Newconstructionofmultilanedividedhighwayswherethemainlinepavementisasphaltpavement.
2.
Overlayor3Rtypeprojectsonexistingmultilanedividedhighwayswheretheasphaltpavementoverlayis3inchesormore.
3.
OverlaytypeprojectsonexistingNationalHighwaySystem(NHS)highwayswheretheasphaltpavementoverlayis3inchesormore.
4.
ProjectsonotherhighwayswhereapprovedbytheDeputyStateHighwayEngineerforDevelopmentorOperations.
Marshallasphaltpavementwillbeusedonallotherprojects.
Forresurfacingprojects,polymer-modifiedasphalt(PMA)maybeusedintheAsphaltPavementatthediscretionoftheDistrictEngineer/ManagerortheDirectoroftheEngineeringDivisiononprojectswhereconventionalasphaltpavementhasexhibitedsevereruttingorDD-6443of11shovingproblemsduetoheavytrafficconditions,suchas:(1)Intersectionswithveryheavytrucktraffic,(2)Truckclimbinglanesandramps,(3)ForthesurfaceliftofasphaltpavementsinresurfacingprojectswherethedesignESALSexceed30,000,000,Otherwise,PMAisrequiredtobeusedinthefollowingcases:(1)Forthesurfacelift(atminimum)ofasphaltpavementinnewconstructionprojectswherethedesignESALsexceed30,000,000(RefertoDD646–PavementDesignGuide)andthepavementsystemisbeingdesignedasa"perpetual"or"longlife"system.
PreferablyPMAshouldbeusedinthetop4"ofthepavementstructurefora"perpetual"or"longlife"pavementsystem,(2)Forthesurfaceliftonroadwaysfacilitatingaccesstoindustrialparks,warehouses,productionfacilities,etc.
(3)HighPerformanceThinOverlay(HPTO)asphaltpavementinaccordancewithSpecialProvision496.
ThespecifiedbindergradeshallbeaPG76-22withpolymer-modification.
PMAcanbeusedasalongtermsolutiontosevereruttingproblems.
DuetothesignificantadditionalcostofPMA,donotuseitonanyprojectwithoutfirstrepairingbasefailuresandremovingexcessivelyruttedpavement.
PMAshouldgenerallybeusedonlyintheskidsurfacemix(preferablya12.
5mmmix),butmayalsobeusedintheunderlyingbasecoursedependingontheseverityofthetrafficconditions.
AlwaysusethepreferredthicknessfromtheSuperpaveasphaltpavementrecommendedliftthicknesstablesasaminimumthicknesswhenusingPMA.
AnymixdesigntobeusedasascratchcourseshallnotbespecifiedtousePMA.
EitherSuperpaveorMarshallasphaltpavementshouldnormallybeusedexclusivelyonaproject.
Therewillbenoprojectswherebothspecificationsareused,unlessapprovedbytheappropriateDeputyStateHighwayEngineer,orashereinafterprovided.
TheDesignermayconsiderusingbothSuperpaveandMarshallasphaltpavementwhenalargequantityofeachtype(>5000tonsofeachtypeonacontract)couldbespecifiedinthesamecontract.
Thissituationcanoccurwhenthereisenoughlengthofsideroadstobepavedinthecontracttoallowmorethan5000tonsofMarshallmixtobeused.
Properbiditemsandalternatesforbothtypesofasphaltpavementmixwillthenbeincludedinthecontract.
RoadwaysthatwillbeconstructedofMarshallasphaltpavementwillbeindicatedassuchintheAsphaltSummaryTableandonthetypicalsectionsforeachroadway.
IfthedesignerdoesnotdesireMarshallasphaltpavementtobeused,thennoitemsandalternatesforthismixwillbeindicatedinthecontract.
Onoverlayor3Rprojectswhichrequirepavementand/orbasefailurerepairstobemadebeforetheoverlayisplaced,thedesignershallindicatewhichmixtype(SuperpaveorMarshall)istobeusedfortheserepairs,andincludeproperbiditemsandquantitiesinthecontract.
Ifmixtypesubstitutionsareallowedbythedesigner,thenalternatebiditemsandquantitieswillbeincludedinthecontractasshownintheexamplebelow.
Thepavementmethoddesigntype,DD-6444of11"HMA",aggregatealternate,andmixtypeisindicatedintheexamplebelowforillustrativepurposesonly.
Example:AA1401001-020MARSHALLHMABASECRSE,SG,TY2,TN(PavementRepair)AA2401001-021MARSHALLHMABASECRSE,S,TY2,TN(PavementRepair)BB1401001-042SUPERPAVEHMABASECRSE,SG,TY25,TN(PavementRepair)BB2401001-043SUPERPAVEHMABASECRSE,S,TY25,TN(PavementRepair)DETERMINATIONOF"EQUIVALENTSINGLEAXLELOAD"(ESAL)COUNTThe"ESALCalculator"programshallbeusedtocalculatethe20yearprojecteddesignESALsforallprojectsunlessoneofthefollowingapplies.
1.
The"ESALCalculator"programproducesavalueexceeding10,000,000.
2.
Whenatrafficstudyhasbeenperformed.
(i.
e.
WhentrafficmovementsortrafficcountsareprovidedbytheTrafficModelingandAnalysisUnitofthePlanningDivision.
)3.
Onroadwayrealignmentprojectsthatexceed1000feetofrelocatedroadway.
4.
Whenthereisanexpecteddevelopmentintheareathatmaychangeoralterthenatureorcharacteroftheexpectedtraffic.
(i.
e.
Shoppingcenters,schools,etc.
)5.
TheprojectisontheCRTS(CoalandResourceTransportationSystem).
The"ESALCalculator"programcanbeobtainedfromtheTechnicalSectionoftheEngineeringDivisionorontheWestVirginiaDepartmentofTransportation'swebsiteathttp://www.
transportation.
wv.
gov/highways/engineering/Pages/Manuals.
aspx,thenunderthe"Paving"headingchoose"ESALCalculator".
A.
Whenthe"ESALCalculator"programcannotbeusedtocalculatetheESALsthentheESALsorthepercentageoftrafficineachofthe13classesshallbeobtainedfromtheTrafficModelingandAnalysisUnitofthePlanningDivision.
ThedesigneriscautionedthatthedevelopmentofappropriatedatatoestablishaccurateESALcountsmayrequiresignificantleadtime.
TheTrafficModelingandAnalysisUnitofthePlanningDivisionshouldthereforebenotifiedasearlyaspossiblesotheymaysupplytheinformation.
PLANREQUIREMENTSProjectsusingeitherSuperpaveorMarshallasphaltpavementwillshowthe20yearprojecteddesignESALsonboththegeneralnotessheetandthetypicalsectionsheet(s)showingthepavementdetails.
Thisincludesnewconstruction,reconstruction,DD-6445of11ANDresurfacingprojects(includingALLbridgereplacementprojectsregardlessofthelengthofpavementplaced).
ThedesignESALsshallbeshownforthemainlineandallotheraffectedroadwayswheremorethan500feetofpavementisbeingplaced.
A.
SuperpaveAsphaltPavementThePGBindergradewillnormallybeoneofthestandardgradesspecifiedinSection401.
2ofthestandardspecifications.
However,ifaprojectrequirestheuseofanonstandardgrade,thebindergrade(s)shallbeprovidedonboththegeneralnotessheetandthetypicalsectionsheet(s)showingthepavementdetails.
B.
MarshallAsphaltPavementProjectsusingMarshallasphaltpavement,includingDistrict-designedprojects,willdesignatetheuseof"MediumMixDesign"or"HeavyMixDesign"aswellasthedesignESALsonboththegeneralnotessheetandthetypicalsectionsheet(s)showingthepavementdetails.
Thedesignershouldnotethattheterms"Medium"and"Heavy"refertoEquivalentSingleAxleLoads(ESALs),andnottothequalityoftheasphaltpavement.
AfterdeterminingtheESALsbyeitherusingtheESALCalculatororobtainingthevaluefromthePlanningDivision,themixdesigntypeshallbedeterminedfromthefollowingcriteria.
MediumMixDesign-Thisdesignisintendedforuseonlocalserviceroadsorruralresurfacingprojectswitha20-yearprojecteddesignESALsoflessthan3,000,000.
HeavyMixDesign-Thisdesignisintendedforuseonnewconstructionprojectsandonprojectswitha20yearprojecteddesignESALsofequaltoorgreaterthan3,000,000.
ESTIMATINGQUANTITIESA.
AsphaltPavementThequantityforasphaltpavementshallbeestimatedat1.
980ton/cyforstoneandgravelmixes,1.
890ton/cyforslagmixesand2.
10ton/cyforsteelslagmixes.
B.
PatchingandLevelingThequantityforPatchingandLevelingCourseshallbeestimatedbymultiplyingthenominaldepthoftheirregularitytoberepairedplusinchbytheirregularity'ssurfacearea.
Thentheconversionratesof1.
980ton/cyforstoneandgravelmixes,1.
890ton/cyforslagmixesand2.
10ton/cyforsteelslagmixeswillbeutilized.
C.
ScratchCourseThequantityforScratchCourseshallbeestimatedatathicknessofone-halfinch(0.
028ton/sy)fortheentireareatobecoveredwithScratchCourse.
DD-6446of11D.
AsphaltMaterial(TackCoat)ThequantityforAsphaltMaterial(TackCoat)shallbeestimatedasindicatedinTable408.
11inthelatestissueoftheStandardSpecifications.
Noapplicationratewillbeshownonthetypicalsections.
E.
CoverAggregateCoveraggregatewillbeusedbythecontractorwhennecessaryasdirectedbytheProject'sConstructionEngineer.
Thedesignershallestimatethisitemat10to15lb/syandincludethecostintheunitbidpriceestimateforItem408,AsphaltMaterial.
Noquantityistobeshownintheplans.
TYPESELECTIONA.
PatchingandLevelingGeneral:PatchingandLevelingistobeplacedatvariouslocationsthroughouttheprojecttoremoveirregularitiesintheexistingpavement,suchasdips,ortoraisetheoutsideedgeoftheexistingpavementtoprovideauniformtemplatepriortoplacingabaseorwearingcourse.
PatchingandLevelingshallnotbespecifiedasacontinuouslayerorcoursetobeplacedoverthefullwidthandlengthoftheproject.
ProjectSelection:PatchingandLevelingshouldbeusedonlyinresurfacingorrehabilitationprojects,notintheconstructionofnewpavements.
Itshallbespecifiedwhenthedeviationsintheexistingpavementare1inchorgreaterindepth.
TypicalSections:PatchingandLevelingshallbeshownontheplantypicalsectionsasalayerwiththicknessspecifiedas"variable-2"maximumliftthickness.
Noapplicationrateshallbeshown.
PatchingandLevelingthicknessisnotincludedinthestructuraldesignofthepavement.
B.
ScratchCourseGeneral:ScratchCourseshallbespecifiedwhenthedeviationsintheexistingpavementarelessthan1inchindepth.
ScratchCoursecanbeplacedovertheentireprojectortothelimitsestablishedbythedesigner.
IftheScratchCourseisnottobeplacedoverthefullwidthoftheproject,itshouldbespecifiedatleastatafulllanewidth.
AlthoughScratchCoursecanbeplacedoverthecompleteproject,itisnotaconstantthicknesslayer.
Theterm"ScratchCourse"comesfromthemethodofplacementofthisitem.
Thepavingequipmentissettodragonor"scratch"thehighareasoftheexistingpavement,onlydepositingmaterialinthelowareas;therebycreatingasmoothsurfaceonwhichtoplacethenextlayerofasphaltpavement.
Ifmillingisperformedontheproject,ScratchCourseshouldnotbenecessary.
TheDesignershouldspecifyScratchCourseinthecontractiftheoverlayisthefirstoverlayoveranexistingPortlandCementConcretePavement(PCCP),orifpreviousasphaltpavementoverlayswillbemilleddeepenoughtoexposetheoriginalPCCP.
ThisDD-6447of11willnotincludenewlyconstructedPCCPorapproachslabs.
ProjectSelection:ScratchCourseisnormallyusedinrehabilitationorresurfacingprojects.
ScratchCoursemaybespecifiedtobeplacedontopofType1orType37.
5BaseCoursespriortoplacingthefinalwearingorskidcourseinnewconstructionprojects,ifaType2oraType19BaseCourseisnotusedasthetopliftofthebasecourses.
TypicalSections:ScratchCourseshallbeshownontheplantypicalsectionsasalinewithoutathicknessorapplicationrate.
ScratchCourseisnotincludedinthestructuraldesignofthepavement.
C.
BaseCoursesGeneral:ItisrecommendedthatinmultiliftpavementswhenType1orType37.
5BaseCourseisused,thetopliftofbasecoursebeaType2or19toimprovethesmoothnessofthefinishedpavement.
ThiswouldeliminatetheuseofaScratchCoursepriortoplacingthefinalwearingorskidcourse.
1.
MarshallAsphaltPavementa.
Type1BaseCourseshallbespecifiedwhenthetotalbasecoursethicknessfornewconstructionisgreaterthan3.
25inches.
Onresurfacingprojects,Type1BaseCourseshallnotbespecifiedwheretemporarytrafficcontrolrequirementsprohibitanedgedropoffof3inches.
b.
Type2BaseCourseshallbespecifiedwhenthetotalbasecoursethicknessislessthanorequalto3.
25inches.
RecommendedLiftThicknessforMarshallAsphaltPavementMixTypeAggregateNominalMaximumSizeMinimumLiftThicknessMaximumLiftThicknessPreferredThickness20.
75inch(19mm)2.
0inches(50mm)3.
0inches(75mm)2.
0inches(50mm)11.
5inches(37.
5mm)3.
25inches(82mm)5.
0inches(125mm)4.
0inches(100mm)2.
SuperpaveAsphaltPavementa.
Type37.
5BaseCourseshallbespecifiedwhenthetotalbasecoursethicknessfornewconstructionisgreaterthanorequalto4.
5inches.
Onresurfacingprojects,Type37.
5BaseCourseshallnotbespecifiedwheretemporarytrafficcontrolrequirementsprohibitanedgedropoffof3inches.
b.
Type19or25BaseCourseshallbespecifiedwhenthetotalbasecoursethicknessislessthan4.
5inches.
DD-6448of11RecommendedLiftThicknessforSuperpaveAsphaltPavementMixTypeMarshallEquivalentDesignationsAggregateNominalMaximumSizeMinimumLiftThicknessMaximumLiftThicknessPreferredThickness**19Base-20.
75inch(19mm)2.
25inches(56mm)3.
5inches(88mm)2.
5inches(63mm)25HeavyDutyBase-21inch(25mm)3.
0inches(75mm)4.
0inches(100mm)3.
5inches(88mm)37.
5Base-11.
5inches(37.
5mm)4.
5inches(113mm)6.
0inches(150mm)5.
0inches(125mm)**Min.
ThicknesswithPolymerModifiedBindersD.
WearingCoursesGeneral:Thewearingcourseisasingleliftconstantthicknesscoursetobeplacedovertheentirepavementsurface.
Thewearingcourseistheridingsurfaceonwhichtraffictravels.
Type4orType19WearingCourseisintendedforuseinheavytrucktrafficsituations.
OnprojectswithacurrentADTof3000ormorevehiclesperday,thewearingcourseshallbeaskidresistantmixinaccordancewithSection402oftheStandardSpecifications.
OnlyType1,Type4,Type9.
5,Type12.
5orType19shallbespecifiedasaskidresistantmix.
1.
MarshallAsphaltPavementRecommendedLiftThicknessforMarshallAsphaltPavementWearingorSkidMixTypeAggregateNominalMaximumSizeMinimumLiftThicknessMaximumLiftThicknessPreferredThickness3No.
4(4.
75mm)0.
5inch(12.
5mm)0.
75inch(19mm)5/8inch(16mm)13/8inch(9.
5mm)1.
0inch*(25mm)1.
5inches*(37.
5mm)1.
0inch*(25mm)40.
75inch(19mm)2.
0inches(50mm)2.
0inches(50mm)2.
0inches(50mm)*1inch(37.
5mm)thicknessonresurfacingprojectswheretheWearingCourseistheonlyasphaltpavementmaterialbeingplacedexclusiveofPatching&LevelingandScratchCourses.
DD-6449of112.
SuperpaveAsphaltPavementRecommendedLiftThicknessForSuperpaveAsphaltPavementWearingorSkidMixTypeMarshallEquivalentDesignationsAggregateNominalMaximumSizeMinimumLiftThicknessMaximumLiftThicknessPreferredThickness**4.
75Wearing-3No.
4(4.
75mm)5/8inches(14.
25mm)1.
0inches(24mm)5/8inches(16mm)9.
5Wearing-13/8inch(9.
5mm)1.
5inches*(37.
5mm)2.
0inches*(50mm)1.
5inches*(37.
5mm)12.
5HeavyDutyWearing-1inch(12.
5mm)1.
5inches(37.
5mm)2.
5inches(63mm)2.
0inches(50mm)19Wearing-4inch(19mm)2.
25inches(56mm)3.
5inches(88mm)2.
5inches(63mm)*1inch(37.
5mm)thicknessonresurfacingprojectswheretheWearingCourseistheonlyasphaltpavementmaterialbeingplacedexclusiveofPatching&LevelingandScratchCourses.
**MinimumThicknesswithPolymerModifiedBindersE.
PrimeCoatandAsphaltMaterial(TackCoat)PrimeCoat(Item409)isdiscontinued.
AsphaltMaterial(TackCoat)(Item408)shallbespecifiedforplacementonallexistingpavementpriortoplacingasphaltpavement.
Thisitemshallalsobespecifiedforplacementonnewasphaltpavementwhentrafficmustbemaintainedoneachlayerofasphaltpavementduringconstructionforperiodsoftimeinexcessof2weeks.
F.
MillingexistingpavementsurfacesWhenmillingisspecifiedbythecontract,thethicknessofmillingspecifiedbytheDesignershouldbeatleast"intothelayerjustbelowthelayer(s)beingremoved.
Theintentistomilloffentirelayers,andnotleaveanypartiallayers.
Ifpartiallayersaretoremaininplace,thethicknesstoremainshouldbeatleastoneandone-halftimesthenominaldiameteroftheaggregateoftheexistingasphaltpavementcoursebeingremoved.
Millingisusedtoremovesurfacedistresses,createabetterbondforanoverlay,restorecrossslope,andmaintainverticalgeometricproperties,suchasbridgeclearance,guardrailheight,andgradewithgutterarea.
MillingofAsphaltPavementSurfaces,Section415oftheStandardSpecifications,containsthreetypesofmilling:StandardMilling,FineMilling,andMicromilling.
Thesearedifferentiatedprimarilybythecarbidetoothspacing,typically15,8,and5mmrespectively,resultinginfinertexturedsurfaces.
1.
StandardMillingshallbeusedasthedefaultmillingofasphaltpavement.
ItisintendedtobeusedwhentheDivisionplanstoremoveexistingasphaltpavementwithoutahighlevelofprofileandslopecontrol.
DD-64410of112.
FineMillingshallbeusedwhentheDivisionintendstooverlaythemilledsurfacewithathinliftasphaltcourse.
ItshallalsobeusedwhenthecontractcontainspayitemsfromSection410oftheStandardSpecifications,AsphaltBaseandWearingCourses,PercentWithinLimits(PWL).
Itisintendedbeusedwhencontroloftheprofileandslopeofthemilledsurfaceisimportant.
3.
Micromillingshallbeusedforsmoothnesscorrection,skidcorrection,bumpand/orgradecorrectionsonexistingornewlypavedsurfaces.
Thismillingistypicallylessthananinch.
Itisnotintendedtobeusedwhenstandardoverlaysaretobeused.
SPECIALSITUATIONSGeneral:TheSpecificationshavebeenwrittentoaccountforthemajorityofthesituationsthatwouldoccurduringconstruction.
However,therearealwaysspecialsituationsthatrequirethedesigners'attention.
Specificationrequirementsshouldonlybealteredaftercarefulconsiderationandwhen,intheopinionofthedesigner,thereisnopracticalwayfortheworktobeperformedinaccordancewiththespecifications.
AdditionalnotesthatmodifyexistingspecificationsshallnotbeusedwithouttheapprovaloftheEngineeringDivisionortheDistrictEngineer.
Compaction.
ThespecificationdensityrequirementinthelatestissueoftheStandardSpecificationsshallnotbemodifiedwhenasphaltpavementisplacedatnormalpavingwidths.
Itispossiblethatasphaltpavementwillbeplacedincertainareasoftheprojectwheredensitiesofthismagnitudecannotbeobtained.
Theseareasusuallyhaveanirregularshape,whichwillnotallowtheproperuseofcompactionequipment.
Listedbelowisasituationwherethedensityspecificationmaybemodifiedbyplannoteandtheplannotetobeused.
SituationPlanNoteConcretepavementrepair*CompactiontestingshallbeinaccordancewiththeLot-by-Lotmethodandtherollerpassmethodshallnotbeusedforacceptancetestingforcompaction.
Theengineermayreducethetargetdensityrequirementifthecontractorhasmadeeveryreasonableeffortatobtainingtherequireddensity.
*Iftheproperdensityisnotobtainedduringplacement,trafficwillcontinuetocompacttheasphaltpavementinthepavementrepairarea,causingadditionalsettlement.
Thiswillbeverynoticeablebecausethesurroundingoverlaywillbeplacedontheexistingconcretepavement,whichisrigidandwillnotsettle.
Thedesignerisencouragedtouseconcretetorepairanexistingconcretepavement.
SurfaceTolerance:Tocomplywiththespecifications,projectsreceiving3inchesormoreofasphaltpavementmustmeetasmoothnessrequirement.
ItispossibleDD-64411of11thatasphaltpavementwillbeplacedoncertainprojectsorincertainareasofaprojectwherethisspecificationcannotbemet.
Listedbelowisasituationwherethesurfacetolerancespecificationmaybemodifiedbyplannoteandtheplannotetobeused.
SituationPlanNoteUrbanprojectswithnumeroussidestreetswheretrafficmustcrossthroughthepavingoperation.
ThefirstthreeparagraphsofSection401.
7.
2shallnotapplytothisproject.