作者:标准资料网 时间:2024-05-26 04:37:10   浏览:9655   来源:标准资料网

【英文标准名称】:StandardTestMethodforLoadControlledCyclicTriaxialStrengthofSoil
【原文标准名称】:土壤的负荷控制三向疲劳强度的标准试验方法
【标准号】:ASTMD5311-1992(2004)e1
【标准状态】:现行
【国别】:美国
【发布日期】:1992
【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】:D18.09
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:
【英文主题词】:consolidated-undrainedtests;cohesionlesssoils;laboratorytests;liquefaction;triaxialtests;Axialstrain;Cohesionlesssoil;Consolidated-undrainedtests;Cyclicstrengthtests;Liquefaction;Loadcontrolledcyclictriaxialtechnique;Loadingt
【摘要】:Cyclictriaxialstrengthtestresultsareusedforevaluatingtheabilityofasoiltoresisttheshearstressesinducedinasoilmassduetoearthquakeorothercyclicloading.Cyclictriaxialstrengthtestsmaybeperformedatdifferentvaluesofeffectiveconfiningpressureonisotropicallyconsolidatedspecimenstoprovidedatarequiredforestimatingthecyclicstabilityofasoil.Cyclictriaxialstrengthtestsmaybeperformedatasingleeffectiveconfiningpressure,usuallyequalto14.5lb/in.2(100kN/m2),oralternatepressuresasappropriateonisotropicallyconsolidatedspecimenstocomparecyclicstrengthresultsforaparticularsoiltypewiththatofothersoils,Ref(2).Thecyclictriaxialtestisacommonlyusedtechniquefordeterminingcyclicsoilstrength.Cyclicstrengthdependsuponmanyfactors,includingdensity,confiningpressure,appliedcyclicshearstress,stresshistory,grainstructure,ageofsoildeposit,specimenpreparationprocedure,andthefrequency,uniformity,andshapeofthecyclicwaveform.Thus,closeattentionmustbegiventotestingdetailsandequipment.1.1Thistestmethodcoversthedeterminationofthecyclicstrength(sometimescalledtheliquefactionpotential)ofsaturatedsoilsineitherundisturbedorreconstitutedstatesbytheload-controlledcyclictriaxialtechnique.1.2Thecyclicstrengthofasoilisevaluatedrelativetoanumberoffactors,including:thedevelopmentofaxialstrain,magnitudeofappliedcyclicstress,numberofcyclesofstressapplication,developmentofexcesspore-waterpressure,andstateofeffectivestress.Acomprehensivereviewoffactorsaffectingcyclictriaxialtestresultsiscontainedintheliterature(1).1.3Cyclictriaxialstrengthtestsareconductedunderundrainedconditionstosimulateessentiallyundrainedfieldconditionsduringearthquakeorothercyclicloading.1.4Cyclictriaxialstrengthtestsaredestructive.Failuremaybedefinedonthebasisofthenumberofstresscyclesrequiredtoreachalimitingstrainor100%porepressureratio.SeeSection3forTerminology.1.5Thistestmethodisgenerallyapplicablefortestingcohesionlessfreedrainingsoilsofrelativelyhighpermeability.Whentestingwell-gradedmaterials,silts,orclays,itshouldberecognizedthatpore-waterpressuresmonitoredatthespecimenendstonotingeneralrepresentpore-waterpressurevaluesthroughoutthespecimen.However,thistestmethodmaybefollowedwhentestingmostsoiltypesifcareistakentoensurethatproblemsoilsreceivespecialconsiderationwhentestedandwhentestresultsareevaluated.1.6Therearecertainlimitationsinherentinusingcyclictriaxialteststosimulatethestressandstrainconditionsofasoilelementinthefieldduringanearthquake.1.6.1Nonuniformstressconditionswithinthetestspecimenareimposedbythespecimenendplatens.Thiscancausearedistributionofvoidratiowithinthespecimenduringthetest.1.6.2A90x00B0;changeinthedirectionofthemajorprincipalstressoccursduringthetwohalvesoftheloadingcycleonisotropicallyconsolidatedspecimens.1.6.3Themaximumcyclicshearstressthatcanbeappliedtothespecimeniscontrolledbythestressconditionsattheendofconsolidationandthepore-waterpressuresgeneratedduringtesting.Foranisotropicallyconsolidatedcontractive(volumedecreasing)specimentestedincycliccompression,themaximumcyclicshearstressthatcanbeappliedtothespecimenisequaltoone-halfoftheinitialtotalaxialpressure.Sincecohesionlesssoilsarenotcapableoftak......
【中国标准分类号】:P13
【国际标准分类号】:
【页数】:10P.;A4
【正文语种】:英语