【astm標(biāo)準(zhǔn)】d 5778 - 12

1、Designation:D5778?12StardTestMethodfElectronicFrictionConePiezoconePerationTestingofSoils1ThisstardisissuedunderthefixeddesignationD5778thenumberimmediatelyfollowingthedesignationindicatestheyearofiginaladoptioninthecase

2、ofrevisiontheyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperepsilon()indicatesaneditialchangesincethelastrevisionreapproval.1.Scope1.1Thistestmethodcoverstheprocedurefdeterminingthepointres

3、istanceduringperationofaconicalshapedperometerasitisadvancedintosubsurfacesoilsatasteadyrate.1.2Thistestmethodisalsousedtodeterminethefrictionalresistanceofacylindricalsleevelocatedbehindtheconicalpointasitisadvancedthro

4、ughsubsurfacesoilsatasteadyrate.1.3Thistestmethodappliestofrictionconeperometersoftheelectricelectronictype.FieldtestsusingmechanicaltypeperometersarecoveredelsewherebyTestMethodD3441.1.4Thistestmethodcanbeusedtodetermin

5、epewaterpressuresdevelopedduringtheperationthustermedpiezocone.Pewaterpressuredissipationafterapushcanalsobemonitedfcrelationtotimerateofconsolidationpermeability.1.5Additionalsensssuchasinclinometerseismicgeophones(Test

6、MethodsD7400)resistivityelectricalconductivitydielectrictemperaturesenssmaybeincludedintheperometertoprovideusefulinfmation.Theuseofaninclinometerishighlyrecommendedsinceitwillprovideinfmationonpotentiallydamagingsituati

7、onsduringthesoundingprocess.1.6Coneperationtestdatacanbeusedtointerpretsubsurfacestratigraphythroughuseofsitespecificcrelationstheycanprovidedataonengineeringpropertiesofsoilsintendedfuseindesignconstructionofearthwksfou

8、ndationsfstructures.1.7ThevaluesstatedinSIunitsaretoberegardedasstard.WithinSection13onCalculationsSIunitsareconsideredthestard.Othercommonlyusedunitssuchastheinchpoundsystemareshowninbrackets.Thevariousdatareptedshouldb

9、edisplayedinmutuallycompatibleunitsasagreedtobytheclientuser.Conetipprojectedareaiscommonlyreferredtoinsquarecentimetresfconvenience.Thevaluesstatedineachsystemarenotequivalentstherefeeachsystemshallbeusedindependentlyof

10、theother.NOTE1—Thistestmethoddoesnotincludehydraulicpneumaticperometers.Howevermanyoftheproceduralrequirementshereincouldapplytothoseperometers.AlsooffshemarineCPTsystemsmayhaveproceduraldifferencesbecauseofthedifficulti

11、esoftestinginthoseenvironments(fexampletidalvariationssaltwaterwaves).MechanicalCPTsystemsarecoveredunderTestMethodD3441.1.8Thisstarddoesnotpurpttoaddressallofthesafetyconcernsifanyassociatedwithitsuse.Itistheresponsibil

12、ityoftheuserofthisstardtoestablishappropriatesafetyhealthpracticesdeterminetheapplicabilityofregulatylimitationspritouse.2.ReferencedDocuments2.1ASTMStards:2D653TerminologyRelatingtoSoilRockContainedFluidsD3441TestMethod

13、fMechanicalConePerationTestsofSoil(Withdrawn2014)3D3740PracticefMinimumRequirementsfAgenciesEngagedinTestingInspectionofSoilRockasUsedinEngineeringDesignConstructionD7400TestMethodsfDownholeSeismicTestingE4PracticesfFceV

14、erificationofTestingMachines3.Terminology3.1Definitions:3.1.1DefinitionsareinaccdancewithTerminologyConvention(D653).3.2DefinitionsofTermsSpecifictoThisStard:3.2.1apparentloadtransfer—apparentresistancemeasuredoneitherth

15、econefrictionsleeveofanelectronicconeperometerwhilethatelementisinanoloadconditionbut1ThistestmethodisunderthejurisdictionofASTMCommitteeD18onSoilRockisthedirectresponsibilityofSubcommitteeD18.02onSamplingRelatedFieldTes

16、tingfSoilEvaluations.CurrenteditionapprovedJan.12012.PublishedFebruary2012.iginallyapprovedin1995.Lastpreviouseditionapprovedin2007asD5778–07.DOI:10.1520D577812.2FreferencedASTMstardsvisittheASTMwebsitewww.astm.gcontactA

17、STMCustomerServiceat.FAnnualBookofASTMStardsvolumeinfmationrefertothestard’sDocumentSummarypageontheASTMwebsite.3Thelastapprovedversionofthishisticalstardisreferencedonwww.astm.g.ASummaryofChangessectionappearsattheendof

18、thisstardCopyright?ASTMInternational100BarrHarbDrivePOBoxC700WestConshohockenPA194282959.UnitedStates13.2.28pewaterpressureratioparameterBq—theratioofexcesspewaterpressureatthestardmeasurementlocation?u2tocrectedtotalcon

19、eresistanceqtminusthetotalverticaloverburdenstressσvo(seeEq10).3.2.29pushrods—thethickwalledtubesrodsusedtoadvancetheperometertip.3.2.30sleevefrictionsleevefrictionresistance—sameasfrictionsleeveresistance.3.2.31subtract

20、ionerr—anapparentloadtransferfromtheconetothefrictionsleeveofasubtractiontypeelectronicconeperometercausedbyminvoltagedifferencesinresponsetoloadbetweenthetwostrainelementcells.3.3Abbreviations:3.3.1CPT—abbreviationfthec

21、oneperationtest.3.3.2PCPT(23)CPTu(4)—abbreviationfpiezoconeperationtest(note:symbol“u”addedfpewaterpressuremeasurements).3.3.3CPT—abbreviationfthepiezoconeperationtestwithdissipationphasesofpewaterpressures().3.3.4SCPTu—

22、abbreviationfseismicpiezoconetestTestMethodsD7400(includesonemegeophonestoallowdownholegeophysicalwavevelocitymeasurements).3.3.5RCPTu—abbreviationfresistivitypiezocone(includeselectricalconductivityresistivitymodule).4.

23、SummaryofTestMethod4.1Aperometertipwithaconicalpointhavinga60apexangleaconebaseareaof1015cm2isadvancedthroughthesoilataconstantrateof20mms.Thefceontheconicalpoint(cone)requiredtoperatethesoilismeasuredbyelectricalmethods

24、ataminimumofevery50mmofperation.Improvedresolutionmayoftenbeobtainedat2010mmintervalreadings.Stressiscalculatedbydividingthemeasuredfce(totalconefce)bytheconebaseareatoobtainconeresistanceqc.4.2Africtionsleeveispresenton

25、theperometerimmediatelybehindtheconetipthefceexertedonthefrictionsleeveismeasuredbyelectricalmethodsataminimumofevery50mmofperation.Stressiscalculatedbydividingthemeasuredaxialfcebythesurfaceareaofthefrictionsleevetodete

26、rminesleeveresistancefs.4.3Mostmodernperometersarecapableofregisteringpewaterpressureinducedduringadvancementofthepenetrometertipusinganelectronicpressuretransducer.Theseperometersarecalled“piezocones.”Thepiezoconeisadva

27、ncedatarateof20mmsreadingsaretakenataminimumofevery50mmofperation.Thedissipationofeitherpositivenegativeexcesspewaterpressurecanbemonitedbystoppingperationunloadingthepushrodrecdingpewaterpressureasafunctionoftime.Whenpe

28、waterpressurebecomesconstantitismeasuringtheequilibriumvalue(designatedu0)piezometriclevelatthatdepth.5.SignificanceUse5.1Testsperfmedusingthistestmethodprovideadetailedrecdofconeresistancewhichisusefulfevaluationofsites

29、tratigraphyhomogeneitydepthtofirmlayersvoidscavitiesotherdiscontinuities.Theuseofafrictionsleevepewaterpressureelementcanprovideanestimateofsoilclassificationcrelationswithengineeringpropertiesofsoils.Whenproperlyperfmed

30、atsuitablesitesthetestprovidesarapidmeansfdeterminingsubsurfaceconditions.5.2Thistestmethodprovidesdatausedfestimatingengineeringpropertiesofsoilintendedtohelpwiththedesignconstructionofearthwksthefoundationsfstructurest

31、hebehaviofsoilsunderstaticdynamicloads.5.3Thismethodteststhesoilinsitusoilsamplesarenotobtained.Theinterpretationoftheresultsfromthistestmethodprovidesestimatesofthetypesofsoilperated.Engineersmayobtainsoilsamplesfrompar

32、allelbingsfcrelationpurposesbutpriinfmationexperiencemayprecludetheneedfbings.NOTE3—Thequalityoftheresultsproducedbythisstardisdependentonthecompetenceofthepersonalperfmingthetestthesuitabilityoftheequipmentfacilitiesuse

33、d.AgenciesthatmeetthecriteriaofPracticeD3740aregenerallyconsideredcapableofcompetentobjectivetestingsamplinginspectionetc.UsersofthisstardarecautionedthatcompliancewithPracticeD3740doesnotinitselfassurereliableresults.Re

34、liableresultsdependonmanyfactsPracticeD3740providesameansofevaluatingsomeofthosefacts.6.Interferences6.1Refusaldeflectiondamagetotheperometermayoccurincoarsegrainedsoildepositswithmaximumparticlesizesthatapproachexceedth

35、ediameterofthecone.6.2Partiallylithifiedlithifieddepositsmaycauserefusaldeflectiondamagetotheperometer.6.3Stardpushrodscanbedamagedbrokenunderextremeloadings.Theamountoffcethatpushrodsareabletosustainisafunctionoftheunre

36、strainedlengthoftherodstheweaklinksinthepushrodperometertipstringsuchaspushrodjointspushrodperometertipconnections.Thefceatwhichrodsmaybreakisafunctionoftheequipmentconfigurationgroundconditionsduringpenetration.Excessiv

37、eroddeflectionisthemostcommoncausefrodbreakage.7.Apparatus7.1FrictionConePerometer—Theperometertipshouldmeetrequirementsasgivenbelowin10.1.Inaconventionalfrictiontypeconeperometerthefcesattheconetipfrictionsleevearemeasu

38、redbytwoloadcellswithintheperometer.Eitherindependentloadcellssubtractiontypeperometersareacceptablefuse(Fig.1).7.1.1Inthesubtractiontypeperometertheconesleevebothproducecompressivefcesontheloadcells.Theloadcellsarejoine