Designation:D4546−14StandardTestMethodsforOne-DimensionalSwellorCollapseofSoils1ThisstandardisissuedunderthefixeddesignationD4546;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope*1.1Thisstandardcoverstwolaboratorytestmethodsformeasuringthemagnitudeofone-dimensionalwetting-inducedswellorcollapseofunsaturatedsoilsandonemethodformeasuringload-inducedcompressionsubsequenttowetting-induceddeformation.1.1.1TestMethodAisaprocedureformeasuringone-dimensionalwetting-inducedswellorhydrocompression(col-lapse)ofreconstitutedspecimenssimulatingfieldconditionofcompactedfills.Themagnitudeofswellpressure(themini-mumverticalstressrequiredtopreventswelling),andfreeswell(percentswellunderapressureof1kPaor20lbf/ft2)canalsobedeterminedfromtheresultsofTestMethodA.1.1.2TestMethodBisaprocedureformeasuringone-dimensionalwetting-inducedswellorcollapsedeformationofintactspecimensobtainedfromanaturaldepositorfromanexistingcompactedfill.ThemagnitudeofswellpressureandfreeswellcanalsobedeterminedfromtheresultsofTestMethodB.1.1.3TestMethodCisaprocedureformeasuringload-inducedstrainsonareconstitutedorintactspecimenafterthespecimenhasundergonewetting-inducedswellorcollapsedeformation.1.2InTestMethodA,aseriesofreconstitutedspecimensduplicatingcompactionconditionofthefinefractionofthesoilinthefield(excludingtheoversizeparticles)areassembledinconsolidometerunits.Differentloadscorrespondingtodiffer-entfilldepthsareappliedtodifferentspecimensandeachspecimenisgivenaccesstofreewateruntiltheprocessofprimaryswellorcollapseiscompleted(Fig.1)underaconstantverticaltotalstress(Fig.2).Theresultingswellorcollapsedeformationsaremeasured.Thistestmethodcanbereferredtoaswetting-after-loadingtestsonmultiplereconsti-tutedspecimens.Thedatafromthesetestscanbeusedtoestimateone-dimensionalgroundsurfaceheaveo...
