外文翻译题目:高层建筑学院土木建筑工程学院专业土木工程(建筑工程方向)班级2006级3班学号0603110405姓名赖俊宇指导教师梁新彩二〇一〇年五月19日1TallBuildingsAlthoughtherehavebeenmanyadvancementsinbuildingconstructiontechnologyingeneral,spectacularachievementshavebeenmadeinthedesignandconstructionofultrahigh-risebuildings.Theearlydevelopmentofhigh-risebuildingsbeganwithstructuralsteelframing.Reinforcedconcreteandstressed-skintubesystemshavesincebeeneconomicallyandcompetitivelyusedinanumberofstructuresforbothresidentialandcommercialpurposes.Thehigh-risebuildingsrangingfrom50to110storiesthatarebeingbuiltallovertheUnitedStatesaretheresultofinnovationsanddevelopmentofnewstructuralsystems.Greaterheightentailsincreasedcolumnandbeamsizestomakebuildingsmorerigidsothatunderwindloadtheywillnotswaybeyondanacceptablelimit.Excessivelateralswaymaycauseseriousrecurringdamagetopartitions,ceilings,andotherarchitecturaldetails.Inaddition,excessiveswaymaycausediscomforttotheoccupantsofthebuildingbecauseoftheirperceptionofsuchmotion.Structuralsystemsofreinforcedconcrete,aswellassteel,takefulladvantageoftheinherentpotentialstiffnessofthetotalbuildingandthereforedonotrequireadditionalstiffeningtolimitthesway.Inasteelstructure,forexample,theeconomycanbedefinedintermsofthetotalaveragequantityofsteelpersquarefootoffloorareaofthebuilding.CurveAinFig.1representstheaverageunitweightofaconventionalframewithincreasingnumbersofstories.CurveBrepresentstheaveragesteelweightiftheframeisprotectedfromalllateralloads.Thegapbetweentheupperboundaryandthelowerboundaryrepresentsthepremiumforheightforthetraditionalcolumn-and-beamframe;Structuralengineershavedevelopedstructuralsystemswithaviewtoeliminatingthispremium.Systemsinsteel.Tallbuildingsinsteeldevelopedasaresultofseveraltypesofstructuralinnovations.Theinnovationshavebeenappliedtotheconstructionofbothofficeandapartmentbuildings.Frameswithrigidbelttrusses.Inordertotietheexteriorcolumnsofaframestructuretotheinteriorverticaltrusses,asystemofrigidbelttrussesatmid-heightandatthetopofthebuildingmaybeused.AgoodexampleofthissystemistheFirstWisconsinBankBuilding(1974)inMilwaukee.Framedtube.Themaximumefficiencyofthetotalstructureofatallbuilding,forboth2strengthandstiffness,toresistwindloadcanbeachievedonlyifallcolumnelementscanbeconnectedtoeachotherinsuchawaythattheentirebuildingactsasahollowtubeorrigidboxinprojectingoutoftheground.Thisparticularstructuralsystemwasprobablyusedforthefirsttimeinthe43-storyreinforcedconcreteDeWittChestnutApartmentBuildinginChicago.Themostsignificantuseofthissystemisinthetwinstructuralsteeltowersofthe110-storyWorldTradeCenterbuildinginNewYork.Column-diagonaltrusstube.Theexteriorcolumnsofabuildingcanbespacedreasonablyfarapartandyetbemadetoworktogetherasatubebyconnectingthemwith.Diagonalmembersintersectingatthecenterlineofthecolumnsandbeams.ThissimpleyetextremelyefficientsystemwasusedforthefirsttimeontheJohnHancockCenterinChicago,usingasmuchsteelasisnormallyneededforatraditionalstorybuilding.Fig.1.Graphicalrelationshipbetweendesignquantitiesofsteelandbuildingheightsforatypicalbuildingframe.CurvesAandBcorrespondtotheboundaryconditionsindicatedinthetwobuildingdiagrams.1psf=0.048kPa.Bundledtube.Withthecontinuingneedforlargerandtallerbuildings,theframedtubeorthecolumn-diagonaltrusstubemaybeusedinabundledformtocreatelargertubeenvelopeswhilemaintaininghighefficiency.Thei10-storySearsRoebuckHeadquartersBuildinginChicagohasninetubes,bundledattilebaseofthebuildinginthreerows.Someoftheseindividualtubesterminateatdifferentheightsofthebuilding,demonstratingtheunlimitedarchitecturalpossibilitiesofthislateststructuralconcept.TheSearstower,ataheightof1450ft(442m),istheworld'stallestbuilding.Stressed-skintubesystem.Thetubestructuralsystemwasdevelopedforimprovingtheresistancetolateralforces(windorearthquake)andthecontrolofdrift(lateralbuildingmovement)inhigh-risebuilding.Thestressed-skintubetakesthetubesystemastepfurther.Thedevelopmentofthestressed-skintubeutilizesthefacadeofthebuildingasastructuralelementwhichactswiththeframedtube,thusprovidinganefficientwayofresistinglateralloadsinhigh-risebuildings,andresultingincost-effectivecolumn-freeinteriorspacewithahighratioofnettogrossfloorarea.Becauseofthecontributionofthestressed-skinfacade,theframedmembersofthetuberequirelessmass,andarethuslighterandlessexpensive.Allthetypicalcolumnsandspandrelbeamsarestandardrolledshapes,minimizingtheuseandcostofspecialbuilt-upmembers.Thedepthrequirementfortheperimeterspandrelbeamsisalsoreduced,andtheneedforupsetbeamsabovefloors,whichwouldencroachonvaluablespace,isminimized.Thestructuralsystemhasbeenusedonthe54-storyOneMellonBankCenterinPittsburgh.3Systemsinconcrete.Whiletallbuildingsconstructedofsteelhadanearlystart,developmentoftallbuildingsofreinforcedconcreteprogressedatafastenoughratetoprovideacompetitivechallengetostructuralsteelsystemsforbothofficeandapartmentbuildings.Framedtube.Asdiscussedabove,thefirstframedtubeconceptfortallbuildingswasusedforthe43-storyDeWittChestnutApartmentBuilding.Inthisbuilding,exteriorcolumnswerespacedat5.5-ft(1.68-m)centers,andinteriorcolumn