Designation:D6521−22StandardPracticeforAcceleratedAgingofAsphaltBinderUsingaPressurizedAgingVessel(PAV)1ThisstandardisissuedunderthefixeddesignationD6521;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thispracticecoverstheconditioningofasphaltbinderstosimulateacceleratedaging(oxidation)bymeansofpressur-izedairandelevatedtemperature.Thisisintendedtosimulatethechangesinrheologywhichoccurinasphaltbindersduringin-serviceoxidativeaging,butmaynotaccuratelysimulatetherelativeratesofaging.ItisnormallyintendedforusewithresiduefromTestMethodD2872(RTFOT),whichisdesignedtosimulateplantaging.NOTE1—PAVconditioninghasnotbeenvalidatedformaterialscontainingparticulatematerials.1.2Theagingofasphaltbindersduringserviceisaffectedbyambienttemperatureandbymixture-associatedvariables,suchasthevolumetricproportionsofthemix,thepermeabilityofthemix,propertiesoftheaggregates,andpossiblyotherfactors.Thisconditioningprocessisintendedtoprovideanevaluationoftherelativeresistanceofdifferentasphaltbinderstooxidativeagingatselectedelevatedagingtemperaturesandpressures,butcannotaccountformixturevariablesorprovidetherelativeresistancetoagingatin-serviceconditions.1.3ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.4Thetextofthisstandardreferencesnotesandfootnoteswhichprovideexplanatorymaterial.Thesenotesandfootnotes(excludingthoseintablesandfigures)shallnotbeconsideredasrequirementsofthestandardNOTE2—Thequalityoftheresultsproducedbythisstandardaredependentonthecompetenceofthepersonnelperformingtheprocedureandthecapability,calibration,andmaintenanceoftheequipmentused.AgenciesthatmeetthecriteriaofSpecificationD3666aregenerallyconsideredcapableofcompetentandobjectivetesting,sampling,inspection,etc.Usersofthisstandardarecautionedt...
