【英文标准名称】:StandardPracticeforRapidDryingofCompactedAsphaltSpecimensUsingVacuumDryingApparatus
【原文标准名称】:用真空干燥器对紧凑型沥青样本快速干燥的标准实施规程
【标准号】:ASTMD7227-2006
【标准状态】:现行
【国别】:
【发布日期】:2006
【实施或试行日期】:
【发布单位】:美国材料与试验协会(US-ASTM)
【起草单位】:D04.21
【标准类型】:(Practice)
【标准水平】:()
【中文主题词】:器具;地沥青;紧凑型;干燥;样品;真空干燥
【英文主题词】:
【摘要】:Specimendryweightisacriticalmeasureindeterminationofaccuratedensityandmanyothertestsintheconstructionandrawmaterialsindustries.Dryingspecimensatroomtemperatureisrequiredforsometestsandprovidesanadvantageforotherteststoensuretheintegrityandtopreservethecharacteristicsofspecimens.Thispracticecoversdryingcompactedasphaltspecimensinavacuumchamberthatiscapableofkeepingthespecimenatclosetoroomtemperature.Avacuumpumpreducesthepressureinsidethechamber,thusallowingwatertoevaporateatlowtemperature.Sincethespecimennaturallycoolsduringtheevaporationprocess,makingwaterhardertoevaporate,itisimportanttohavepropertemperaturecontrolsinthechambertoensurespecimenremainsatclosetoroomtemperature.Automaticcontrolswithintheunitallowthespecimentoremainatclosetoroomtemperaturebyperiodicallyallowingaflowofwarmairtoenterthevacuumchamber.Cyclingbetweenvacuumandairflowconditionsallowsthespecimentodryinashortperiodoftime.Completelysaturatedspecimenswithover30gofretainedwatercanbedriedinabout30minutes.Formostfieldcoresthatarenotcompletelysaturatedthedryingtimeisgenerallylessthan15minutes.Note18212;Cycletime(period)candependonthematerialcomposition.Eachcycleinvolvesanalternatingperiodof30to180secondsofvacuumoperationand30to120secondsofairflow.Thismethodcanbeusedfor100mmdiameter,150mmdiametercylindrical,andcubicalcompactedbituminousspecimens.Thismethodcanalsobeusedfordryinglooseasphaltmixtures,aggregatesamplesandothersolidspecimens.Followmanufacturersrecommendedproceduresfordryingspecimensotherthancompactedbituminousspecimens.Thismethodcanbeusedtodeterminemoisturecontentandamountofwaterlossduringdryingbyweighingthesamplebeforeandafterthedryingoperations.1.1Thispracticecoverstheprocessofdryingcompactedasphaltspecimensusingvacuumdryingapparatus.1.2Thespecimensdriedbythispracticeremainatroomtemperature,whichhelpsinmaintainingspecimenintegrityduringthedryingprocess.1.3Thispracticecanbeusedforcompactedcylindricalandcubicalbituminouslaboratoryandfieldspecimens1.4Thispracticecanalsobeusedfordryingotherconstructionmaterialssuchasconcrete,soils,aggregatesandlooseasphaltmixtures.Usemanufacturersrecommendationsfordryingotherconstructionmaterials.1.5ThevaluesstatedinSIunitsaretoberegardedasthestandard.Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatoryrequirementspriortouse.
【中国标准分类号】:E43
【国际标准分类号】:91_100_50
【页数】:3P.;A4
【正文语种】: