建筑技术ArchitectureTechnology第54卷第4期2023年2月Vol.54No.4Feb.2023·474·大跨径预应力混凝土部分斜拉桥合龙对顶施工控制研究肖宏笛，史晓贞，黄精，陈仁贵（武汉华中科大检测科技有限公司，430074，武汉）摘要：由于混凝土收缩徐变及温差效应的影响，大跨径预应力混凝土矮塔斜拉桥在施工及运营过程中不可避免地会产生下挠，从而引起墩顶的纵向偏位，使墩底产生较大次内力。为了消除这种不利影响，通常在中跨合龙前，对跨中合龙段主梁施加一对对顶力，来抵消塔墩纵向偏位产生的不利影响。以剑潭东江特大桥为背景，建立该桥三维有限元模型，分析混凝土收缩徐变及温差效应产生的塔墩偏移量。根据计算塔墩偏移量确定顶推力，设计合理顶推装置。监控结果表明，对顶效应实测结果与计算结果吻合较好，对顶合龙达到了抵消收缩徐变及温差效应产生的不利影响的效果。关键词：部分斜拉桥；合龙；对顶；收缩徐变；温度效应；施工控制中图分类号：TU758.11文献标志码：A文章编号：1000-4726(2023)04-0474-03rEsEArcHoNcoNsTrucTioNcoNTroloFclosurETEcHNiQuEsForpArTiAllycABlED-sTAyEDprEsTrEssEDcoNcrETEBriDGEwiTHloNGspANXIAOHong-di,SHIXiao-zhen,HUAnGJing,CHEnRen-gui(WuhanHuazhongUniversityofscienceandTechnologyTestingTechnologyCo.,Ltd.,430074,Wuhan,China)Abstract:Duetotheconcretecreepshrinkageandtemperatureeffect,deflectionofprestressedextradosedcable-stayedbridgewithlongspanisinevitableduringconstructionandoperationalcourse,whichcancausethelongitudinaldeflectionofpiertopandthesecondaryinternalforceofpierbottom.Toeliminatethenegativeeffect,pairsofliftingforcesareusuallyappliedtothemainbeamofthemid-spanbeforeclosure.Inthispaper,athree-dimensionalfiniteelementmodelisestablishedbasedontheJiantanDongjiangbridgetoanalyzethedeviationoftowerpierscausedbyconcretecreepshrinkageandtemperatureeffect.Afterthat,thethrustisdeterminedbytheoffsetoftowerpierandthereasonablethrustdeviceisdesigned.Themonitoringresultsshowthatthemeasuredresultsareingoodagreementwiththecalculatedresults,andthenegativeeffectofconcretecreepshrinkageandtemperatureiseliminated.Keywords:partiallycabled-stayedbridge;closure;counter-thrust;shrinkageandcreep;temperatureeffect;constructioncontrol...
