【英文标准名称】:StandardTestMethodsforDeterminationoftheSoilWaterChararcteristicCurveforDesorptionUsingaHangingColumn,PressureExtractor,ChilledMirrorHygrometer,and/orCentrifuge
【原文标准名称】:使用悬垂柱、压力萃取器、冷镜式湿度计和/或离心分离机测定土壤水解吸性能曲线的标准试验方法
【标准号】:ASTMD6836-2002
【标准状态】:现行
【国别】:
【发布日期】:2002
【实施或试行日期】:
【发布单位】:美国材料与试验协会(ASTM)
【起草单位】:D18.04
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:离心机;柱;曲面;解吸;测定;萃取器;湿度计;镜子;压力;土壤水;土壤
【英文主题词】:capillarypressure;chilledmirrorhygrometer;gravimetricwatercontent;hangingcolumn;matricpotential;matricsuction;pressuremembrane;pressureplate;soil;soilwatercharacteristiccurve;suction;totalsuction;volumetricwatercontent;wateractivity;
【摘要】:Thesoilwatercharacteristiccurve(SWCC)isfundamentaltohydrologicalcharacterizationofunsaturatedsoilsandisrequiredformostanalysesofwatermovementinunsaturatedsoils.TheSWCCisalsousedincharacterizingtheshearstrengthandcompressibilityofunsaturatedsoils.TheunsaturatedhydraulicconductivityofsoilisoftenestimatedusingpropertiesoftheSWCCandthesaturatedhydraulicconductivity.Thismethodappliesonlytosoilscontainingtwoporefluids:agasandaliquid.Theliquidisusuallywaterandthegasisusuallyair.Otherliquidsmayalsobeused,butcautionmustbeexercisediftheliquidbeingusedcausesexcessiveshrinkageorswellingofthesoilmatrix.Afullinvestigationhasnotbeenconductedregardingthecorrelationbetweensoilwatercharacteristiccurvesobtainedusingthismethodandsoilwatercharacteristicscurvesofin-placematerials.Thus,resultsobtainedfromthismethodshouldbeappliedtofieldsituationswithcautionandbyqualifiedpersonnel.Note18212;Thequalityoftheresultproducedbythisstandarddependsonthecompetenceofthepersonnelperformingthetestandthesuitabilityoftheequipmentandfacilitiesused.AgenciesthatmeetthecriteriaofPracticeD3740aregenerallyconsideredcapableofcompetentandobjectivetesting,sampling,inspection,etc.UsersofthisstandardarecautionedthatcompliancewithPracticeD3740doesnotinitselfensurereliableresults.Reliableresultsdependonmanyfactors.PracticeD3740providesameansofevaluatingsomeofthesefactors.1.1Thistestmethodcoversthedeterminationofsoilwatercharacteristiccurves(SWCCs)fordesorption(drying).SWCCsdescribetherelationshipbetweensuctionandvolumetricwatercontent,gravimetricwatercontent,ordegreeofwatersaturation.SWCCsarealsoreferredtoassoilwaterretentioncurves,soilwaterreleasecurves,orcapillarypressurecurves.1.2Thisstandarddescribesfivemethods(A-E)fordeterminingthesoilwatercharacteristiccurve.MethodA(hangingcolumn)issuitableformakingdeterminationsforsuctionsintherangeof0to80kPa.MethodB(pressurechamberwithvolumetricmeasurement)andMethodC(pressurechamberwithgravimetricmeasurement)aresuitableforsuctionsintherangeof0to1500kPa.MethodD(chilledmirrorhygrometer)issuitableformakingdeterminationsforsuctionsintherangeof500kPato100MPa.MethodE(centrifugemethod)issuitableformakingdeterminationsintherange0to120kPa.MethodAtypicallyisusedforcoarsesoilswithlittlefinesthatdrainreadily.MethodsBandCtypicallyareusedforfinersoilswhichretainwatermoretightly.MethodDisusedwhensuctionsnearsaturationarenotrequiredandcommonlyisemployedtodefinethedryendofthesoilwatercharacteristiccurve(thatis,watercontentscorrespondingtosuctions>1000kPa).MethodEistypicallyusedforcoarsersoilswhereanappreciableamountofwatercanbeextractedwithsuctionsupto120kPa.Themethodsmaybecombinedtoprovideadetaileddescriptionofthesoilwatercharacteristiccurve.Inthisapplication,MethodAorEisusedtodefinethesoilwatercharacteristiccurveatlowersuctions(0to80kPaforA,0to120kPaforE)nearsaturationandtoaccuratelyidentifytheairentrysuction,MethodBorCisusedtodefinethesoilwatercharacteristiccurveforintermediatewatercontentsandsuctions(100to1000kPa),andMethodDisusedtodefinethesoilwatercharacteristiccurvesatlowwatercontentsandhighersuctions(>1000kPa)and1.3AllobservedandcalculatedvaluesshallconformtotheguideforsignificantdigitsandroundingestablishedinPracticeD6026.TheproceduresinPracticeD6026......
【中国标准分类号】:B11
【国际标准分类号】:13_080_40
【页数】:20P.;A4
【正文语种】: