外文翻译建筑的组成部分.doc -- 5 元

河北科技师范学院毕业论文（设计）错误未找到引用源。题目ComponentsofABuildingandTallBuildings学生姓名指导教师系别错误未找到引用源。专业班级河北科技师范学院教务处制1ComponentsofABuildingandTallBuildings1.AbstractMaterialsandstructuralformsarecombinedtomakeupthevariouspartsofabuilding,includingtheloadcarryingframe,skin,floors,andpartitions.Thebuildingalsohasmechanicalandelectricalsystems,suchaselevators,heatingandcoolingsystems,andlightingsystems.Thesuperstructureisthatpartofabuildingaboveground,andthesubstructureandfoundationisthatpartofabuildingbelowground.Theskyscraperowesitsexistencetotwodevelopmentsofthe19thcenturysteelskeletonconstructionandthepassengerelevator.SteelasaconstructionmaterialdatesfromtheintroductionoftheBessemerconverterin1885.GustaveEiffel18321932introducedsteelconstructioninFrance.HisdesignsfortheGaleriedesMachinesandtheTowerfortheParisExpositionof1889expressedthelightnessofthesteelframework.TheEiffelTower,984feet300metershigh,wasthetalleststructurebuiltbymanandwasnotsurpasseduntil40yearslaterbyaseriesofAmericanskyscrapers.ElishaOtisinstalledthefirstelevatorinadepartmentstoreinNewYorkin1857.In1889,EiffelinstalledthefirstelevatorsonagrandscaleintheEiffelTower,whosehydraulicelevatorscouldtransport2,350passengerstothesummiteveryhour.2.LoadCarryingFrameUntilthelate19thcentury,theexteriorwallsofabuildingwereusedasbearingwallstosupportthefloors.Thisconstructionisessentiallyapostandlinteltype,anditisstillusedinframeconstructionforhouses.Bearingwallconstructionlimitedtheheightofbuildingbecauseoftheenormouswallthicknessrequiredforinstance,the16storyMonadnockBuildingbuiltinthe1880sinChicagohadwalls5feet1.5metersthickatthelowerfloors.In1883,WilliamLeBaronJenney18321907supportedfloorsoncastironcolumnstoformacagelikeconstruction.Skeletonconstruction,consistingofsteelbeamsandcolumns,wasfirstusedin1889.Asaconsequenceofskeletonconstruction,theenclosingwallsbecomeacurtainwallratherthanservingasupportingfunction.Masonrywasthecurtainwallmaterialuntilthe1930s,whenlightmetalandglasscurtainwallswereused.Aftertheintroductionofbuildingscontinuedtoincreaserapidly.AlltallbuildingswerebuiltwithaskeletonofsteeluntilWorldWarⅡ.Afterthewar,theshortageofsteelandtheimprovedqualityofconcreteledtotallbuildingbeingbuiltofreinforcedconcrete.MarinaTower1962inChicagoisthetallestconcretebuildingintheUnitedStatesitsheight588feet179metersisexceededbythe650foot198meterPostOfficeTowerinLondonandbyothertowers.2Achangeinattitudeaboutskyscraperconstructionhasbroughtareturntotheuseofthebearingwall.InNewYorkCity,theColumbiaBroadcastingSystemBuilding,designedbyEeroSaarinenin1962,hasaperimeterwallconsistingof5foot1.5meterwideconcretecolumnsspaced10feet3metersfromcolumncentertocenter.Thisperimeterwall,ineffect,constitutesabearingwall.OnereasonforthistrendisthatstiffnessagainsttheactionofwindcanbeeconomicallyobtainedbyusingthewallsofthebuildingasatubetheWorldTradeCenterbuildingisanotherexampleofthistubeapproach.Incontrast,rigidframesorverticaltrussesareusuallyprovidedtogivelateralstability.3.SkinTheskinofabuildingconsistsofbothtransparentelementswindowsandopaqueelementswalls.Windowsaretraditionallyglass,althoughplasticsarebeingused,especiallyinschoolswherebreakagecreatesamaintenanceproblem.Thewallelements,whichareusedtocoverthestructureandaresupportedbyit,arebuiltofavarietyofmaterialsbrick,precastconcrete,stone,opaqueglass,plastics,steel,andaluminum.Woodisusedmainlyinhouseconstructionitisnotgenerallyusedforcommercial,industrial,orpublicbuildingbecauseofthefirehazard.4.FloorsTheconstructionofthefloorsinabuildingdependsonthebasicstructuralframethatisused.Insteelskeletonconstruction,floorsareeitherslabsofconcreterestingonsteelbeamsoradeckconsistingofcorrugatedsteelwithaconcretetopping.Inconcreteconstruction,thefloorsareeitherslabsofconcreteonconcretebeamsoraseriesofcloselyspacedconcretebeamsribsintwodirectionstoppedwithathinconcreteslab,givingtheappearanceofawaffleonitsunderside.Thekindoffloorthatisuseddependsonthespanbetweensupportingcolumnsorwallsandthefunctionofthespace.Inanapartmentbuilding,forinstance,wherewallsandcolumnsarespacedat12to18feet3.7to5.5meters,themostpopularconstructionisasolidconcreteslabwithnobeams.Theundersideoftheslabservesastheceilingforthespacebelowit.Corrugatedsteeldecksareoftenusedinofficebuildingsbecausethecorrugations,whenenclosedbyanothersheetofmetal,formductsfortelephoneandelectricallines.5.MechanicalandElectricalSystemsAmodernbuildingnotonlycontainsthespaceforwhichitisintendedoffice,classroom,apartmentbutalsocontainsancillaryspaceformechanicalandelectricalsystemsthathelptoprovideacomfortableenvironment.Theseancillaryspacesinaskyscraperofficebuildingmayconstitute25ofthetotalbuildingarea.Theimportanceofheating,ventilating,electrical,andplumbingsystemsinanofficebuildingisshownbythefactthat40oftheconstructionbudgetisallocatedtothem.Becauseoftheincreaseduseofsealedbuildingwithwindowsthatcannotbeopened,elaboratemechanicalsystemsareprovidedforventilationandairconditioning.Ductsandpipescarryfreshairfromcentralfanroomsandairconditioningmachinery.Theceiling,whichis3suspendedbelowtheupperfloorconstruction,concealstheductworkandcontainsthelightingunits.Electricalwiringforpowerandfortelephonecommunicationmayalsobelocatedinthisceilingspaceormaybeburiedinthefloorconstructioninpipesorconduits.Therehavebeenattemptstoincorporatethemechanicalandelectricalsystemsintothearchitectureofbuildingbyfranklyexpressingthemforexample,theAmericanRepublicInsuranceCompanyBuilding1965inDesMoines,Iowa,exposesboththeductsandthefloorstructureinanorganizedandelegantpatternanddispenseswiththesuspendedceiling.Thistypeofapproachmakesitpossibletoreducethecostofthebuildingandpermitsinnovations,suchasinthespanofthestructure.6.SoilsandFoundationsAllbuildingaresupportedontheground,andthereforethenatureofthesoilbecomesanextremelyimportantconsiderationinthedesignofanybuilding.Thedesignofafoundationdependsonmanysoilfactors,suchastypeofsoil,soilstratification,thicknessofsoillaversandtheircompaction,andgroundwaterconditions.Soilsrarelyhaveasinglecompositiontheygenerallyaremixturesinlayersofvaryingthickness.Forevaluation,soilsaregradedaccordingtoparticlesize,whichincreasesfromsilttoclaytosandtograveltorock.Ingeneral,thelargerparticlesoilswillsupportheavierloadsthanthesmallerones.Thehardestrockcansupportloadsupto100tonspersquarefoot976.5metrictons/sqmeter,butthesoftestsiltcansupportaloadofonly0.25tonpersquarefoot2.44metrictons/sqmeter.Allsoilsbeneaththesurfaceareinastateofcompactionthatis,theyareunderapressurethatisequaltotheweightofthesoilcolumnaboveit.Manysoilsexceptformostsandsandgavelsexhibitelasticpropertiestheydeformwhencompressedunderloadandreboundwhentheloadisremoved.Theelasticityofsoilsisoftentimedependent,thatis,deformationsofthesoiloccuroveralengthoftimewhichmayvaryfromminutestoyearsafteraloadisimposed.Overaperiodoftime,abuildingmaysettleifitimposesaloadonthesoilgreaterthanthenaturalcompactionweightofthesoil.Conversely,abuildingmayheaveifitimposesloadsonthesoilsmallerthanthenaturalcompactionweight.Thesoilmayalsoflowundertheweightofabuildingthatis,ittendstobesqueezedout.Duetoboththecompactionandfloweffects,buildingstendsettle.Unevensettlements,exemplifiedbytheleaningtowersinPisaandBologna,canhavedamagingeffectsthebuildingmaylean,wallsandpartitionsmaycrack,windowsanddoorsmaybecomeinoperative,and,intheextreme,abuildingmaycollapse.Uniformsettlementsarenotsoserious,althoughextremeconditions,suchasthoseinMexicoCity,canhaveseriousconsequences.Overthepast100years,achangeinthegroundwaterleveltherehascausedsomebuildingstosettlemorethan10feet3meters.Becausesuchmovementscanoccurduringandafterconstruction,carefulanalysisofthebehaviorofsoilsunderabuildingisvital.Thegreatvariabilityofsoilshasledtoavarietyofsolutionstothefoundationproblem.Where