2023年全國碩士研究生考試考研英語一試題真題(含答案詳解+作文范文)_第1頁
已閱讀1頁,還剩3頁未讀, 繼續(xù)免費閱讀

下載本文檔

版權(quán)說明:本文檔由用戶提供并上傳,收益歸屬內(nèi)容提供方,若內(nèi)容存在侵權(quán),請進(jìn)行舉報或認(rèn)領(lǐng)

文檔簡介

1、Designation:C1699?09(Reapproved2015)StardTestMethodfMoistureRetentionCurvesofPousBuildingMaterialsUsingPressurePlates1ThisstardisissuedunderthefixeddesignationC1699thenumberimmediatelyfollowingthedesignationindicatesthey

2、earofiginaladoptioninthecaseofrevisiontheyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperepsilon()indicatesaneditialchangesincethelastrevisionreapproval.1.Scope1.1Thistestmethodspecifiesalab

3、atyprocedurefthedeterminationofthewaterretentioncurve(moisturestagecapacity)ofpousbuildingmaterialsatveryhighrelativehuity(RH)levels(≈95to100%RH)crespondingtothecapillarymoistureregionofthesptionisotherm.Thisisachievedby

4、usingthepressureplatetestapparatus.Thistechniquewasiginallydevelopedtostudysoilmoisturecontenteventuallyhadbeenadaptedtobuildingconstructionmaterials.1.2AthigherRHlevels(≈95to100%RH)ofthesptionisotherm(seeTestMethodC1498

5、)useofclimaticchamberisnotanoption.Thistechniqueusesoverpressuretoextractwateroutofthepestructureofpousmaterialsuntilequilibriumbetweenthemoisturecontentinthespecimensthecrespondingoverpressureisachieved.Usingthepressure

6、plateextractsequilibriumcanonlybereachedbydesption.1.3ThevaluesstatedinSIunitsaretoberegardedasstard.Nootherunitsofmeasurementareincludedinthisstard.1.4Thisstarddoesnotpurpttoaddressallofthesafetyconcernsifanyassociatedw

7、ithitsuse.Itistheresponsibilityoftheuserofthisstardtoestablishappropriatesafetyhealthpracticesdeterminetheapplicabilityofregulatylimitationspritouse.2.ReferencedDocuments2.1ASTMStards:2C1498TestMethodfHygroscopicSptionIs

8、othermsofBuildingMaterialsD2325TestMethodfCapillaryMoistureRelationshipsfCoarseMediumTexturedSoilsbyPousPlateApparatus(Withdrawn2007)3D3152TestMethodfCapillaryMoistureRelationshipsfFineTexturedSoilsbyPressureMembraneAppa

9、ratus(Withdrawn2007)3E337TestMethodfMeasuringHuitywithaPsychrometer(theMeasurementofWetDryBulbTemperatures)3.Terminology3.1DefinitionsofTermsSpecifictoThisStard:3.1.1desptionisotherm—thesptionisothermmeasuredexclusivelyd

10、uringthehygroscopicdesptionprocessstartedfromtheconditionoffullwatersaturationofthematerial.3.1.2sptionisotherm—relationshipbetweentherelativehuity(seeTestMethodE337)theequilibriummoisturecontentofthematerialataspecified

11、temperature.3.1.3pressureplatefacility—Heavysteelvesselcapableofholdingdifferentpressurelevels.3.1.4moisturecontentbymass—massofwaterretainedinthespecimendividedbythedrymassofthespecimen.4.SignificanceUse4.1Thepurposeoft

12、histestistoobtainbymeansofaspecifiedlabatyprocedurethevaluesoftheequilibriummoisturecontentathigherRHlevels((≈95to100%).Thesevaluesareusedeitherasmeanstoacterizethematerialasmaterialacteristicsneededasinputtoappropriatec

13、omputermodelsthatcansimulatewettingdryingpotentialofindividualbuildingmaterialsmaterialassembliesunderspecifiedenvironmentalconditions.5.Apparatus5.1Pressurevessel—Heavydutysteelvesselsofapproximately305mmindiameterabout

14、75mm250mmhighwithheavytoplidtightlyheldagainstOringgasketbyclampingbolts(seeFig.1).1ThistestmethodisunderthejurisdictionofASTMCommitteeC16onThermalInsulationisthedirectresponsibilityofSubcommitteeC16.33onInsulationFinish

15、esMoisture.CurrenteditionapprovedMay12015.PublishedAugust2015.iginallyapprovedin2008.Lastpreviouseditionapprovedin2009asC1699–09.DOI:10.1520C169909R15.2FreferencedASTMstardsvisittheASTMwebsitewww.astm.gcontactASTMCustome

16、rServiceat.FAnnualBookofASTMStardsvolumeinfmationrefertothestard’sDocumentSummarypageontheASTMwebsite.3Thelastapprovedversionofthishisticalstardisreferencedonwww.astm.g.Copyright?ASTMInternational100BarrHarbDrivePOBoxC70

17、0WestConshohockenPA194282959.UnitedStates17.9Presseachspecimenfirmlyontheacetateclothensuringgoodcontactalsoremovalofanyairbubblesunderneath.7.10Closethepressureplateextractlidafterensuringgoodconnectionoftheoutflowtubet

18、otheceramicplate.NOTE1—Typicallythefollowingtemperaturesareusedfdryingthetestspecimens:(a)fmaterialswhichdonotchangeeitherstructuredimensionsat105C(221F)fexamplesomemineralmaterialsuse10564C(22168F)(b)fmaterialsinwhichst

19、ructuraldimensionalchangesoccurbetween70C(158F)105C(221F)fexamplesomecellularplasticsuse7062C(15864F)(c)fmaterialsinwhichelevatedtemperaturesbringaboutchemicalphysicalchangesfexamplecrystallinewateringypsumblowingagentso

20、lubilityinsomecellularplasticsuse4062C(10464F)(d)whendryingatthespecifiedafementionedtemperaturesadverselyaffectsthebuildingmaterialdryspecimentomoisturefreeweight(thatisdryweightsee7.1)inadesiccatatroomtemperatureinside

21、anairtightchamberflushedwithdryairhavingadewpointlessthan–40C.NOTE2—Vacuumsaturationleadstothemaximumpossibleequilibriummoisturecontentinamaterialisrelevanttounderwaterbelowgradeconstruction.NOTE3—Capillarysaturationisre

22、levanttoabovegradeconstruction.NOTE4—Kaolinfromaprevioustestmaybereusedsolongasthereisnovisiblecontamination.Theentireamountofdampkaolinshouldbescrapedoftheplateweighed.Distilledwatershouldbeaddedtothemixturetoreturnthei

23、ginalweightof275g(125gkaolin150gofwater)themixtureshouldbewellmixed.8.Procedure8.1Theroomtemperatureshallremainconstantat2261C(7362F)fthedurationofthetest.Ifthelidthebodyoftheextractcoolsdownthencondensationwilloccurinsi

24、dethepressurevesselitwillgiveerroneousresults.8.2Checktheinitialpressuretransducervoltagereadingmakeadjustmentifnecessary.8.3Connecttheexternaloutflowtubetoaflexibleplastictubeplaceitintoaburette’sopeningsoitcanbenotedwh

25、enmoistureequilibriumisobtained.8.4Openaircontrolvalvestoadmitcompressedairgas.Adjustthepressureregulat(seeNote5)untilthedesiredpressureisreachedindertoextractmoisturefromspecimens.Recdthepressure.8.5Bringtestspecimensto

26、equilibriumstateofmoisturecontentfirstatoneofthelowersuctionpressuregiveninTable1consecutivelyatotheruserdeterminedpressurelevels.Equilibriumisachievedwhenthewateroutflow(intheburette)islessthan0.05mLin48hours(seeNote6).

27、8.6Clampoffflexibleplastictube.Releasetheairpressurefromthepressureplateextractopenthelidremovespecimenstoimmediatelydeterminetheirmassesgravimetrically.8.7RewetKaolinpastewithexcessofdistilledwater.Placespecimensbackona

28、ceramicplaterepeatfromstep8.3untilalluserdeterminedsuctionpressuresarecovered.Dependingonthepressurerangesacombinationofseveraldifferentpressureplatesextractswillberequired.Whenmovingfromoneextracttoanotheranewsaturatedc

29、eramicplateisusedalongwithfreshclaypaste.Above15barpressuretheuseofhigherpressuresystemswithcellulosemembranesinsteadofceramicplatesisnecessary.8.8Afterallpressureplatemeasurementsarecompletedplacespecimensinovendrytocon

30、stantweight.Thisfinaldrymass(m0)isusedtocalculatemoisturecontents.NOTE5—Indertoavoidhysteresiseffectitisimptanttomanagetheregulatsothatthedesiredpressureisapproachedfromalowerpressure.Thatisdonotoverpressurethechamberthe

31、nreducethepressuretothedesiredlevel.NOTE6—Dependingonthenatureofthematerialthiscantakeseveraldaysweeksevenmonths.9.Calculation9.1Calculatethemoisturecontentu(kgkg1)feachspecimenateachsuctionpressure(thatisgaugepressure)a

32、sfollows:u5~m2mo!mo(1)m=themassofthespecimenatequilibriummo=thatofthedryspecimen.9.2CalculatetheaveragemoisturecontentU(kgkg1)ofspecimensateachsuctionpressurelevels.9.3Therelativehuity(RH)canbecalculatedeitherfromEq2obta

33、inedfromTable1.Theequilibriumsuctionpressure(Ph)canbeconvertedtotheRH(φ)using:1nφ52MρRTPh(2)M5themolarmassofwaterR5theidealgasconstantT5thethermodynamictemperatureρ5thedensityofwater10.Rept10.1Thetestreptshallincludethef

34、ollowing:10.1.1ReferencetothisASTMStard.10.1.2Productidentification:10.1.2.1Namemanufacturersupplier10.1.2.2Typeasinmanufacturer’sspecification10.1.2.3Productioncodenumberifany10.1.2.4Packaging10.1.2.5Thefminwhichitarriv

35、edatthelabaty10.1.2.6Nominalphysicalacteristicsfexamplebulkdensitythicknessetc.10.1.3Testprocedurewith:10.1.3.1FactsifanywhichhavehadthepotentialtoinfluencetheresultsTABLE1SuctionPressureSetPointsCrespondingRelativeHuity

溫馨提示

  • 1. 本站所有資源如無特殊說明,都需要本地電腦安裝OFFICE2007和PDF閱讀器。圖紙軟件為CAD,CAXA,PROE,UG,SolidWorks等.壓縮文件請下載最新的WinRAR軟件解壓。
  • 2. 本站的文檔不包含任何第三方提供的附件圖紙等,如果需要附件,請聯(lián)系上傳者。文件的所有權(quán)益歸上傳用戶所有。
  • 3. 本站RAR壓縮包中若帶圖紙,網(wǎng)頁內(nèi)容里面會有圖紙預(yù)覽,若沒有圖紙預(yù)覽就沒有圖紙。
  • 4. 未經(jīng)權(quán)益所有人同意不得將文件中的內(nèi)容挪作商業(yè)或盈利用途。
  • 5. 眾賞文庫僅提供信息存儲空間,僅對用戶上傳內(nèi)容的表現(xiàn)方式做保護(hù)處理,對用戶上傳分享的文檔內(nèi)容本身不做任何修改或編輯,并不能對任何下載內(nèi)容負(fù)責(zé)。
  • 6. 下載文件中如有侵權(quán)或不適當(dāng)內(nèi)容,請與我們聯(lián)系,我們立即糾正。
  • 7. 本站不保證下載資源的準(zhǔn)確性、安全性和完整性, 同時也不承擔(dān)用戶因使用這些下載資源對自己和他人造成任何形式的傷害或損失。

評論

0/150

提交評論