武汉绿地中心结构设计与建筑设计的完美结合

399AbstractWuhanGreenlandCenterMainTowerisa125-story,600+metermega-towerinChina.Thetowerstructuralsystemhasbeendevelopedtoharmonizewiththearchitectureasanintegratedwholetomaximizeefficiencyandenhancesafety.Thedistinctivefloor“slots”helpreducethevortexsheddingeffect.Slotlocationswerecoordinatedtoavoidcausingstructuraldiscontinuities.Abovetheroof,steeltrussedtripodlegsrisefromtowerplanwingtipstoseamlesslycompletethebuildingformwithadramaticcrown.DesignchallengesincludeevaluatingbuildingperformanceunderseismiceventsthroughPBDandperformingProgressiveCollapseAnalysestoevaluatestructuralredundancy.Parametricmodelingtoolswereusedtoreducecladdingcostsbymaximizingtheuseoffield-warped,flat-glazedpanelsratherthancostlycurvedglasspanels.Keywords:PBD,PerformanceBasedDesign,ParametricModeling,Outrigger,BeltTruss摘要武汉绿地中心主楼共125层，总高度600米以上。主楼的结构设计追求建筑和结构的完美结合、结构效率的最大化以及安全性的提升。独特的“风槽”的设计有效降低了风旋涡脱落效应。在塔楼顶部，三脚钢桁架沿楼面边缘向上呈汇聚式延伸，在顶部实现无缝对接，形成了一个造型别致的塔冠结构。如何通过基于性能的设计评估建筑抗震性能、如何通过抗连续倒塌分析来评估结构冗余度是本项目结构设计的主要挑战。通过对参数化模型的运用，（建筑幕墙设计者）对平板玻璃现场冷弯的使用达到了最大化，尽可能地避免采用造价昂贵的曲面玻璃，从而减小外幕墙的建造成本。关键词：PBD、基于性能的设计、参数模型、桁架、带状桁架IntroductionThewaveofMega-TallbuildingconstructioninChinastartedwithcitiesalongtheeastcoastandisnowmovinginland.LocatedinWuhan,aninlandcityadjacenttotheYangtzeRiver,theWuhanGreenlandCenterMainTowerisa125-story,600+metermega-towerontracktobethe7thtallestbuildingintheworld,amixed-useskyscraperwithofficesupthroughthe69thfloor,apartmentsatthe70thto89thfloors,ahotelfromthe91stfloortothetopfloorandafive(5)-storydeepbasementhousingthemechanicalspacesplusparking.Locatedatthetowertop,aunique61m-talltowercrownanda35m-talltowerdomehighlightthetower’sdistinctivepersonality.(seeFigure1).ThemajorstructuralsystemofWuhanGreenlandCenterMainTowerconsistingofrobustcompositewalls,giantslightlyslopingcompositeSRCcolumnsandcurvedbelttrusses,isadoptedtoresistthelateralloads(windorseismic)effectively.Thelocationsandgeometryofstructuralcomponentshavebeencarefullyoptimizedtonotonlyprovideenoughstrengthsandstiffnessbutintegratewiththearchitectureseamlessly.引言中国对超高层建筑的追求浪潮始于东面沿岸城市，并逐渐向内地发展。武汉绿地中心主塔将坐落于毗邻长江的内陆城市武汉。塔楼共125层，总高度达600米以上，是一个多功用的超高层建筑，建成后将成为世界第七高楼。主楼底层到69楼用于办公室、70至89层为公寓、91层到顶楼为酒店、另有5层地下室作停车和容纳机电设备之功用。一个高61米的独特塔冠和高35米的穹拱位于塔楼顶部，凸显塔楼独特的建筑风格(参见图1)。为了有效地承担侧向力(风荷载和地震荷载)，武汉绿地中心主楼的主要结构体系包括强大的组合剪力墙、微倾的巨型SRC组合柱和曲线型的环带桁架。结构构件的位置和几何形状都经过了精心地优化以满足强度和刚度的要求，同时与建筑设计达到完美的结合。减少塔群风荷载如同其它的超高层建筑,侧向荷载（含风荷载和地震荷载）在武汉绿地中心主楼的结构设计中起至关重要的作用。根据中国《建筑抗震规范》(GB50011-2010)，武汉位于抗震设防烈度6度区，设计基本地震GuoyongFuJuanBetancurGuoyongFu,DennisPoon&MarkDannettelThorntonTomasettiInc.51MadisonAvenueNewYork,NYUSA10010tel(电话):+1917.661.7800fax(传真):+1917.661.7801email(电子邮箱):[e-mail],[e-mail],[e-mail]符国勇（XueYiFu），宋腾添玛沙帝公司（ThorntonTomasettiInc.）副总裁。他在超高层建筑的结构方面拥有20年的经验,包括上海中心大厦等。DennisPoon,ViceChairmanatThorntonTomasetti,hasover30yearsofexperienceinthedesignofsupertallstructures,andworkedonShanghaiTower.潘子强（DennisPoon），宋腾添玛沙帝公司（ThorntonTomasettiInc.）董事会副主席，在超高层建筑结构设计方面拥有30多年的经验其中包括上海中心大厦的结构设计。Mr.DannettelisaVicePresidentwithThorntonTomasetti,andservesastheregionalleaderforBuildingSkinservicesinthePacificRim.马克·丹纳特（MarkDannettel），宋腾添玛沙帝公司（ThorntonTomasettiInc.）副总裁，主要负责亚洲环太平洋地区的建筑幕墙设计工作。JuanBetancurAdrianSmith+GordonGillArchitecture111WestMonroe,Suite2300Chicago,ILUSA60603tel(电话):+1312.870.4061fax(传真):+1312.920.1775email(电子邮箱):[e-mail]胡安·贝坦库尔（JuanBetancur），AdrianSmith+GordonGill建筑设计公司主管。他在AS+GG和SOM拥有拥有丰富的超高层建筑设计经验。DennisPoonMarkDannettelWuhanGreenlandCenterMainTower:SeamlesslyIntegratingStructureandArchitecture武汉绿地中心主塔:结构设计与建筑设计的完美结合400TowerMassingtoReducetheWindLoadLikeothersupertallbuildings,thelateralloads,windandseismic,playthemostimportantroleinthestructuraldesignofWuhanGreenlandCenterMainTower.AccordingtoChina“CodeforSeismicDesignofBuildings“(GB50011-2010),WuhanislocatedintheSeismicFortificationZone#6,withdesigngroundaccelerationspecifiedas0.05gundermoderateearthquake,whichisdefinedasaearthquakewith“10%ExceedanceProbabilityin50-year”oranearthquakewith475-yearreturnperiod.RWDIperformedwindtunnelteststodeterminethestructuralwindloadsfortowerstrengthandstiffnessdesign.Forthestrengthdesignsofthetowerstructure,the100-yearwindloadandseismicloadunderfrequentearthquake,whichisdefinedas“63%ExceedanceProbabilityin50-year”oranearthquakewith50-yearreturnperiod,shallbecombinedwithgravityload.Unlikemostbuildingcodes,inwhichtheseismicloadcasenevercombineswiththewindloadcase,thefrequentearthquakeloadforthistowerneedstobecombinedwith100-yearwindloadasper“TechnicalSpecificationforConcreteStructuresofTallBuilding“(JGJ3-2010).TheTable1liststhe100-yearwindloadandcode-basefrequentearthquakeload.FromTable1,thebaseshearandoverturningmomentundera100-yearwindloadismuch