ASTM D5918-2006 土壤对冻胀和解冻变弱敏感性的标准试验方法

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【英文标准名称】:StandardTestMethodsforFrostHeaveandThawWeakeningSusceptibilityofSoils
【原文标准名称】:土壤对冻胀和解冻变弱敏感性的标准试验方法
【标准号】:ASTMD5918-2006
【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】:D18.19
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:土壤组分;耐霜冻性;试验;融解
【英文主题词】:freeze-thawtest;frostsusceptibility;roadsandrunways;soilandaggregate;thawweakeningsusceptibility
【摘要】:Thesetestmethodscanbeusedtodeterminetherelativefrost-susceptibilityofsoilsusedinpavementsystems.Boththefrostheavesusceptibilityandthethawweakeningsusceptibilitycanbedetermined.Thesetestmethodsshouldbeusedonlyforseasonalfrostconditionsandnotforpermanentorlong-termfreezingofsoil.Thesetestmethodsalsohavenotbeenvalidatedforanythingotherthanpavementsystems.Thesetestmethodscannotbeusedtopredicttheamountoffrostheaveorthawweakeninginthefield.Itspurposeistodeterminetherelativefrost-susceptibilityclassificationforuseinempiricalpavementdesignmethodsforseasonalfrostregions.1.1Theselaboratorytestmethodscoverthefrostheaveandthawweakeningsusceptibilitiesofsoilthatistestedinthelaboratorybycomparingtheheaverateandthawedbearingratiowithvaluesinanestablishedclassificationsystem.Thistestwasdevelopedtoclassifythefrostsusceptibilityofsoilsusedinpavements.Itshouldbeusedforsoilswherefrost-susceptibilityconsiderations,basedonparticlesizesuchasthelimitof3%finerthan20mminSpecificationD2940,areuncertain.Thisismostimportantforfrost-susceptibilitycriteriasuchasthoseusedbytheCorpsofEngineers,thatrequireafreezingtestforaggregatesofinconclusivefrostclassification.Thefrostheavesusceptibilityisdeterminedfromtheheaverateduringfreezing.Thethawweakeningsusceptibilityisdeterminedwiththebearingratiotest(seeTestMethodD1883).1.2Thisisanindextestforestimatingtherelativedegreeoffrost-susceptibilityofsoilsusedinpavementsystems.Itcannotbeusedtopredicttheamountoffrostheavenorthestrengthafterthawing,norcanitbeusedforapplicationsinvolvinglong-termfreezingofpermafrostorforfoundationsofrefrigeratedstructures.1.3Thetestmethodsdescribedareforonespecimenandusesmanualtemperaturecontrol.Itissuggestedthatfourspecimensbetestedsimultaneouslyandthatthetemperaturecontrolanddatatakingbeautomatedusingacomputer.1.4AllrecordedandcalculatedvaluesshallconformtotheguideforsignificantdigitsandroundingestablishedinPracticeD6026.1.4.1Theproceduresusedtospecifyhowdataarecollected/recordedandcalculatedinthisstandardareregardedastheindustrystandard.Inaddition,theyarerepresentativeofthesignificantdigitsthatshouldgenerallyberetained.Theproceduresuseddonotconsidermaterialvariation,purposeforobtainingthedata,specialpurposestudies,oranyconsiderationsfortheusersobjectives;anditiscommonpracticetoincreaseorreducesignificantdigitsofreporteddatatobecommensuratewiththeseconsiderations.Itisbeyondthescopeofthisstandardtoconsidersignificantdigitsusedinanalysismethodsforengineeringdesign.1.4.2Measurementsmadetomoresignificantdigitsorbettersensitivitythanspecifiedinthisstandardshallnotberegardedanonconformancewiththisstandard.1.5ThisStandardiswrittenusingSIunits.Inch-poundunitsareprovidedforconvenience.Thevaluesstatedininchpoundunitsmaynotbeexactequivalents;therefore,theyshallbeusedindependentlyoftheSIsystem.Combiningvaluesfromthetwosystemsmayresultinnonconformancewiththisstandard.1.5.1Thegravitationalsystemofinch-poundunitsisusedwhendealingwithinch-poundunits.Inthissystem,thepound(lbf)representsaunitofforce(weight),whiletheunitformassisslugs.Therationalizedslugunitisnotgiven,unlessdynamic(F=ma)calculationsareinvolved.1.5.2Itiscommonpracticeintheengineering/constructionprofessiontoconcurrentlyusepoundstorepresentbothaunitofmass(lbm)andofforce(lbf).Thisimplicitlycombinestwoseparatesystemsofunits;thatis,the......
【中国标准分类号】:B11
【国际标准分类号】:13_080_01
【页数】:12P.;A4
【正文语种】: