土木工程专业外文翻译--高层结构与钢结构.doc

土木工程专业外文翻译--高层结构与钢结构.doc土木工程专业外文翻译一高层结构与钢结构外文原文TallingbuildingandSteelconstructionAlthoughtherehavebeenmanyadvancementsinbuildingconstructiontechnologyingeneralSpectaculararchievementshavebeenmadeinthedesignandconstructionofultrahigh-risebuiIdingsTheearlydevelopmentofhigh-risebuildingsbeganwithstruetuTa’lsteelframingReinforcedconcreteandstressed-mercialpurposesThehigh-ptionofsuchmotionStrueturalsystemsofreinforcedconcreteaswellassteeltakefulladvantageofinherentpotentialstiffnessofthetotalbuildingandthereforerequireadditionalstiffeningtolimittheswayInasteelstructureforexampletheeconomycanbedefinedintermsofthetotalaveragequantityofsteelpersquarefootoffloorareaofthebuildingCurveAinFig1representstheaverageunitweightofaconventionalframewithincreasingnumbersofstoriesCurveBrepresentstheaveragesteelweightiftheframeisprotectedfromalllateralloadsThegapbetweentheupperboundaryandthelowerboundaryrepresentsthepremiumforheightforthetraditionalcolumn-and-beamframcStructuralengineershavedevelopedstructuralsystemswithaviewtoeliminatingthispremiumSystemsinsteelTallbuildingsinsteeldevelopedasaresuItofseveraltypesofstructuralinnovationsTheinnovationshavebeenappliedtotheconstruetionofbothofficeandapartmentbuildingsFramewithrigidbelttrussesInordertotietheexteriorcolumnsofaframestructurctotheintcriorverticaltrussesasystemofrigidbelttrussesatmid-heightandatthetopofthebuildingmaybeusedAgoodexampleofthissystemistheFirstWisconsinBankBuilding1974inMilwaukeeFramedtubeTheimumefficiencyofthetotalstructureofatallbuildingforbothstrengthandstiffnesstoresistwindloadcanbeachievedonlyifallcolumnelementcanbeconnectedtoeachotherinsuchawaythattheentirebuildingactsasahollowtubeorrigidboxinprojectingoutofthegroundThisparticularstructuralsystemwasprobablyusedforthefirsttimeinthe43-storyreinforcedconcreteDeWittChestnutApartmentBuildinginChicagoThemostsignificantuseofthissystemisinthetwinstructuralsteeltowersofthe110-storyWorldTradeCenterbuildinginNewYorkColumn-diagonaltrusstubeTheexteriorcolumnsofabuildingcanbespacedreasonablyfarapar