研讨房屋建筑毕业设计 4外文翻译

'　　研讨房屋建筑毕业设计4外文翻译研讨房屋建筑毕业设计4外文翻译_论文范文导读：hecracksduetothetransferofforcesfromthetensilereinforcementtotheconcretethroughbond.Thiscontributionofthetensileconcreteisknoember'sstiffnessaftercrackingandhencethedeflectionofthememberandtheorslabeventhoughconcretecontinuestocarrytensilestressbetthetensilereinforcementtotheconcretethroughbond.Thiscontributionofthetensileconcreteisknoember'sstiffnessaftercrackingandhencethedeflectionofthememberandtheemberssuchasfloorslabstheflexuralstiffnessofafullycrackedsectionismanytimessmallerthanthatofanuncrackedsectionandtensionstiffeningcontributesgreatlytothepostcrackingstiffness.InthispapertheapproachestoaccountfortensionstiffeningintheACIEuropeanandBritishcodesareevaluatedcriticallyandpredictionsareparedentalobservations.Finallyremendationsareincludedform5678910研讨房屋建筑毕业设计4外文翻译_论文范文(2)导读：suallyneglectedorslabeventhoughconcretecontinuestocarrytensil5678910odelingtensionstiffeninginthedesignofreinforcedconcretefloorslabsfordeflectioncontrol.CEDatabasesubjectheadings:Cracking;Creep;Deflection;Concrete reinforced;Serviceability;Shrinkage;Concreteslabs.1ProfessorofCivilEngineeringSchoolofCivilandEnvironmentalEngineeringUniv.ofNeber007.Separatediscussionsmustbesubmittedforindividualpapers.Toextendtheclosingdatebyonemonthaustbefiledanuscriptforthistechnicalnoteittedforrevieber282006.ThistechnicalnoteispartoftheJournalofStructuralEngineeringVol.133No.6June007.11ProfessorofCivilEngineeringSchoolofCivilandEnvironmentalEngineeringUniv.ofNeorslabeventhoughconcretecontinuestocarrytensil5678910研讨房屋建筑毕业设计4外文翻译_论文范文(3)导读：orcementreinforcedconcreteslabsusuallycontainrelativelysmallquantitiesoftensilereinforcementoftenclosetotheminimumamountpermittedbytherelevantbuildingcode.Forsuch memberstheflexuralstiffnessofafullycrackedcrosssectionismanytimessmallerthanthatofanuncrackedcrossestressbetthetensilereinforcementtotheconcretethroughbond.Thiscontributionofthetensileconcreteisknoember'sstiffnessaftercrackingandhenceitsdeflectionandtheentreinforcedconcreteslabsusuallycontainrelativelysmallquantitiesoftensilereinforcementoftenclosetotheminimumamountpermittedbytherelevantbuildingcode.Forsuch memberstheflexuralstiffnessofafullycrackedcrosssectionismanytimessmallerthanthatofanuncrackedcrosssectionandtensionstiffeningcontributesgreatlytothestiffnessaftercracking.Indesigndeflectionandcrackcontrolatservice-loadlevelsareusuallythegoverningconsiderationsandaccuratemodelingofthestiffnessaftercrackingisrequired.Themostmonlyusedapproachindeflectioncalculationsinvolvesdetermininganaverageeffectivemomentofinertia[Ie]foracrackedmember.SeveraldifferentempiricalequationsareavailableforIeincludingtheendedinACI318[ACI2005].Othermodelsfor5678910研讨房屋建筑毕业设计4外文翻译_论文范文(4)导读：tensilestressintheconcreteatthesectionofmaximummomentre5678910tensionstiffeningareincludedinEurocode2[CEN1992]andthe[BritishStandardBS81101985].RecentlyBischoff[2005]demonstratedthatBranson'sequationgrosslyoverestimatesthtieaveragesffnessofreinforcedconcretememberscontainingsmallquantitiesofsteelreinforcementandheproposedanalternativeequationforIeodelsareevaluatedcriticallyandempiricalpredictionsareparedeasureddeflections.Finallyremendationsformodelingtensionstiffeninginstructuraldesignareincluded.2.FlexuralResponseafterCrackingConsidertheload-deflectionresponseofasimplysupportedreinforcedconcreteslabshoemberisuncrackedandbehaveshomogeneouslyandelasticallyandtheslopeoftheloaddeflectionplotisproportionaltothemomentofinertiaoftheuncrackedtransformedsectionIuncr.ThememberfirstcracksatPcrefibertensilestressintheconcreteatthesectionofmaximummomentre5678910研讨房屋建筑毕业设计4外文翻译_论文范文(5)导读：gthoftheconcreteormodulusofrupturefr.Thereisasuddenchangeinthelocalstiffnessatandimmediayadjacentto thisfirstcrack.Onthesectioncontainingthecracktheflexuralstiffnessdropssignificantlybutmuchofthebeamremainsuncracked.Asloadincreasesmorecracksformandthachestheflexuraltensilestrengthoftheconcreteormodulusofrupturefr.Thereisasuddenchangeinthelocalstiffnessatandimmediayadjacentto thisfirstcrack.Onthesectioncontainingthecracktheflexuralstiffnessdropssignificantlybutmuchofthebeamremainsuncracked.Asloadincreasesmorecracksformandtheaverageflexuralstiffnessoftheentirememberdecreases.Ifthetensileconcreteinthecrackedregionsofthebeamcarriednostresstheload-deflectionrelationshipefibertensilestressintheconcreteremainedatfraftercrackingtheloaddeflectionrelationshipesandisshoorecracksdevelopandtheactualresponsetendstoberofcrackshasstabilized.Forslabscontainingsmallquantitieso5678910研讨房屋建筑毕业设计4外文翻译_论文范文(6)导读：dsection;Ig=momentofinertiaofthegrosscrosssectionaboutthecentroidalaxis;Ma=maximummomentinthememberatthestagedefle5678910ftensilereinforcement[typicallytensionstiffeningmayberesponsibleformorethan50%ofthestiffnessofthecrackedmemberatserviceloadsandremainssignificantuptoandbeyondthepointateloadisapproached].Thetensionstiffeningeffectdecreaseseundersustainedloadsprobablyduetothebinedeffectsoftensilecreepcreepruptureandshrinkagecrackingandthismustbeaccountedforinlong-termdeflectioncalculations.3.ModelsforTensionStiffeningTheinstantaneousdeflectionofbeamorslabatserviceloadsmaybecalculatedfromelastictheoryusingtheelasticmodulusofconcreteEcandaneffectivemomentofinertiaIe.ThevalueofIeforthememberisthevaluecalculatedusingEq.[1]atmidspanforasimplysupportedmemberandaomentregionsofacontinuousspan（1）omentofinertiaofthecrackedtransformedsection;Ig=momentofinertiaofthegrosscrosssectionaboutthecentroidalaxis[butmorecorrectlyshouldbethemomentofinertiaoftheuncrackedtransformedsectionIuncr];Ma=maximummomentinthememberatthestagedefle5678910研讨房屋建筑毕业设计4外文翻译_论文范文(7)导读：cefromthecentroidalaxisofthegrosssectiontotheextremefiberintension.AmodificationoftheACIapproachisincludedintheAustralianStandardAS3600-2001(AS2001)toaccountforthefactthatshrinkage-inducedtensionintheconcretemayreducethecrackingmomentsignificantly.Thecrctionisputed; Mcr=crackingmoment=(frIg/yt);fr=modulusofruptureofconcrete(=7.5fcinpsiand0.6fcinMpa);andyt=distancefromthecentroidalaxisofthegrosssectiontotheextremefiberintension.AmodificationoftheACIapproachisincludedintheAustralianStandardAS3600-2001(AS2001)toaccountforthefactthatshrinkage-inducedtensionintheconcretemayreducethecrackingmomentsignificantly.ThecrackingmomentisgivenbyMcr=(frfcs)Ig/ytaximumshrinkage-inducedtensilestressintheuncrackedsectionattheextremefibreatomentlevelanddegreeofcrackingandisgivenby（3）and1=1.0fordeformedbarsand0.5forplainbars;2=1.0forasingleshort-termloadand0.5forrepeatedorsustainedloading;sr=stressinthetensilereinforcementattheloadingcausingfirstcracking(i.e.omentequalsMcr)calculatedentstressatloadingunderconsideration(i.e.omentMsisacting)calculatedwhileignoringconcreteintension;cr=curvatureatthesectionwhileig5678910研讨房屋建筑毕业设计4外文翻译_论文范文(8)导读：linearelastic;and（3）thestressdistributionforconcreteintensionistriangularhavingavalueofzeroattheneutralaxisandavalueatthecentroidofthetensilesteelof1.0MPainstantaneouslyreducingto0.55MPainthelongterm. 4.pariso5678910noringconcreteintension;anduncr=curvatureontheuncrackedtransformedsection.Forslabsinpureflexureifthepressiveconcreteandthereinforcementarebothlinearandelastictheratiosr/sinEq.(3)isequaltotheratioMcr/Ms.UsingthenotationofEq.（1）Eq.(2)canbereexpressedas（4）ForaflexuralmembercontainingdeformedbarsundershorttermloadingEq.(3)bees=1（Mcr/Ms）2andEq.（4）canberearrangedtogivethefollodeflectioncalculations[recentlyproposedbyBischoff(2005)]:(5)Thisapproachingthat(1)planesectionsremainplane;(2)theconcreteinpressionandthereinforcementareassumedtobelinearelastic;and（3）thestressdistributionforconcreteintensionistriangularhavingavalueofzeroattheneutralaxisandavalueatthecentroidofthetensilesteelof1.0MPainstantaneouslyreducingto0.55MPainthelongterm. 4.pariso5678910研讨房屋建筑毕业设计4外文翻译_论文范文(9)导读：;0.01areparedaticofrectangularsection850mmentataneffectivedepthd(inalyieldnentalDataTotesttheapplicabilityoftheACI318Eurocode2andBS8110approachesforlightlyreinforcedconcretemembersthemeasuredmomentversusdeflectionresponsefor11simplysupportedsinglyreinforcedone-aticofrectangularsection850mmentataneffectivedepthd(inalyieldstressfsy=500Mpa).DetailsofeachslabaregiveninTable1includingrelevantgeometricandmaterialproperties.Thepredictedandmeasureddeflectionsatmidspanforeachslabomentatmidspanequals1.11.2and1.3McrarepresentedinTable2.Themeasuredmomentversusinstantaneousdeflectionresponseatmidspanoftwooftheslabs(SS2andZ3)areparedwiththecalculatedresponsesobtainedusingthethreecodeapproachesinFig.2.Alsoshownaretheresponsesifcrackingdidnotoccurandiftensionstiffeningwasignored.5.DiscussionofResultsItisevidentthatforthese5678910研讨房屋建筑毕业设计4外文翻译_论文范文(10)导读：einforcedslabstensionstiffeningisverysignificantprovidingalargeproportionofthepostcrackingstiffness.FromTable2theratioofthemidspandeflectionobtainedbyignoringtensionstiffeningtothemeasuredmidspandeflection(overthemomentrangeMcrto1.3Mcr)isintherange1.38-3lightlyreinforcedslabstensionstiffeningisverysignificantprovidingalargeproportionofthepostcrackingstiffness.FromTable2theratioofthemidspandeflectionobtainedbyignoringtensionstiffeningtothemeasuredmidspandeflection(overthemomentrangeMcrto1.3Mcr)isintherange1.38-3.69eanvalueof2.12.Thatisonaveragetensionstiffeningcontributesmorethan50%oftheinstantaneousstiffnessofalightlyreinforcedslabaftercrackingatserviceload.ForeveryslabtheACI318approachunderestimatestheinstantaneousdeflectionaftercracking particularlysoforlightlyreinforcedslabs.InadditionACI318doesnotmodeltheabruptchangeindirectionofthemoment-deflectionresponseatfirstcrackingnordoesitpredictthecorrectshapeofthepostcrackingmoment-deflectioncurve.Theunderestimationofshort-termdeflectionusingtheACI318modelisconsiderablygreaterinpracticethanthatindicatedbythelaboratorytestsreportedhere.UnliketheEurocode2andBS8110approachestheACI318modeldoesnotrecognizeoraccountforthereductioninthecrackingmomentthatwillinevitablyoccurinpracticeduetotensioninducedin234567891011'