标准资料网-标准资料免费资源平台

【英文标准名称】:StandardGuideforCalculatingInSituEquivalentElasticModuliofPavementMaterialsUsingLayeredElasticTheory
【原文标准名称】:使用多层弹性理论计算筑路材料原位相等弹性模量的标准指南
【标准号】:ASTMD5858-1996(2008)
【标准状态】:现行
【国别】:美国
【发布日期】:1996
【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】:E17.41
【标准类型】:(Guide)
【标准水平】:()
【中文主题词】:
【英文主题词】:backcalculation;deflectionbasin;layeredelastictheory;NDT(nondestructivedeflectiontesting);pavementmoduli;Backcalculation;Deflection--pavementsurfaces/applications;Deflectionbasin;Elasticmodulus;Layeredelastictheory;Nondestructiv
【摘要】:Thisguideisintendedtopresenttheelementsofanapproachforestimatinglayermodulifromdeflectionmeasurementsthatmaythenbeusedforpavementevaluationoroverlaydesign.Tocharacterizethematerialsinthelayersofapavementstructure,onefundamentalinputparametermeasuredinthelaboratoryandusedbysomeoverlaydesignproceduresistheresilientmodulus.Deflectionanalysisprovidesatechniquethatmaybeusedtoestimatetheinsituequivalentlayerelasticmoduliofapavementstructureasopposedtomeasuringtheresilientmoduliinthelaboratoryofsmallandsometimesdisturbedsamples.Formanyoverlaydesignproceduresthatarebasedonlayeredelastictheory,theresilientmodulusisapproximatedbythisequivalentlayerelasticmodulus,becausetheequivalentmodulusisdeterminedasanaveragevalueforthetotallayerattheinsitustressconditionsofanactualpavement.Itshouldbeemphasizedthatlayermodulicalculatedwiththisprocedureareforaspecificloadingconditionandfortheenvironmentalconditionsatthetimeoftesting.Forthesemodulitobeusedinpavementevaluationsandoverlaydesign,adjustmentstoareferencetemperature,season,anddesignloadmayberequired.Theseadjustmentsarenotapartofthisguide.Theunderlyingassumptionusedinthesolutionisthatarepresentativesetoflayermoduliexistsfortheparticularloadingcondition(magnitudeandarea)andtemperaturecondition,suchthatthetheoreticalorcalculateddeflectionbasin(usingquasi-staticlayeredelastictheoryandtheassumedstaticloadcharacteristicsoftheNDTdevice)closelyapproximatesthemeasureddeflectionbasin.Inreality,dependingonthetoleranceallowedintheprocedureandtherelativenumberoflayerscomparedtothenumberofdeflectionsensors,severalcombinationsofmodulimaycausethetwobasinstox201C;matchx201D;(orbewithintolerance)reasonablywell.Acertaindegreeofengineeringjudgementisnecessarytoevaluatethesealternativesolutionsandselectthemostapplicablecombinationoreliminateunreasonablesolutions,orboth.Therehavebeenseveralstudiesthatcomparedtheresultsofvarioustypesofequipmentandanalysismethods;unfortunately,considerablevariabilityhasbeennoted.Atthistime,noprecisionestimatehasbeenobtainedfromastatistically-designedseriesoftestswithdifferentx201C;knownx201D;materialsandlayerthicknesses.Thebackcalculatedresultsdovarysignificantlywiththevariousassumptionsusedinanalysistoemulatetheactualconditionaswellaswiththetechniquesusedtoproduceandmeasurethedeflections.Sincetheguidedealswithacomputerizedanalyticalmethod,therepeatabilityisexcellentiftheinputdataandparametersremainthesame.Thebiasoftheprocedurecannotbeestablishedatthistime.Theidentityofthex201C;truex201D;insitumodulus,basedonresilientmodulustestingorsomeotherfieldorlaboratorytest,needstobestandardizedbeforethebiasofthemethodcanbeestablished.1.1Thisguidecoverstheconceptsforcalculatingtheinsituequivalentlayerelasticmodulicanbeusedforpavementevaluation,rehabilitationandoverlaydesign.Theresultingequivalentelasticmodulicalculatedfromthedeflectiondataaremethod-dependentandrepresentthestiffnessesofthelayersunderaspecificnondestructivedeflectiontesting(NDT)deviceatthatparticulartestloadandfrequency,temperature,andotherenvironmentalandsite-specificconditions.Adjustmentsfordes......
【中国标准分类号】:Q20
【国际标准分类号】:
【页数】:7P.;A4
【正文语种】:英语