跨京广铁路信阳编组场大桥施工控制关键技术  

Key Construction Control Techniques for a Bridge Crossing Beijing-Guangzhou Railway in Xinyang Marshaling Yard

作　　者：陈锋 李新伟 李泽露 张美玲 CHEN Feng;LI Xinwei;LI Zelu;ZHANG Meiling(Xinyang Chengfa Road and Bridge Construction Development Co.,Ltd.,Xinyang 464000,China;China Railway Bridge Science Research Institute,Ltd.,Wuhan 430034,China;National Key Laboratory for Bridge Intelligent and Green Construction,Wuhan 430034,China)

机构地区：[1]信阳城发路桥建设开发有限公司,河南信阳464000 [2]中铁大桥科学研究院有限公司,湖北武汉430034 [3]桥梁智能与绿色建造全国重点实验室,湖北武汉430034

出　　处：《世界桥梁》2023年第4期50-56,共7页World Bridges

摘　　要：跨京广铁路信阳编组场大桥为(150+150)m独塔曲线钢箱梁斜拉桥,塔高86 m,向曲线外倾斜3°。该桥采用不平衡水平转体法施工,转体重量达19600 t,转体角度74°。针对斜塔施工过程中结构重心外移引起的倾覆稳定问题,以及斜塔曲梁斜拉索初张拉钢梁脱架难的问题,采用MIDAS Civil软件建立桥梁施工过程有限元模型,进行施工控制研究。施工过程中,采用砂筒+配重措施,以提高结构抗倾覆系数至1.303,保证桥塔施工过程的稳定性;提前拆除塔根处钢梁支架,减小斜拉索初张力,保证了钢梁安全顺利脱架,同时避免了钢梁扭转;运用桥梁转体智能监测控制技术实时监测转体过程,转速控制为0.65(°)/min,转体过程平顺稳定,成桥后监测的主梁线形与斜拉索索力均满足规范要求。The bridge in Xinyang Marshaling Yard that crosses the Beijing-Guangzhou Railway is a curved steel box girder cable-stayed bridge,featuring a pylon that rises 86 m,inclines 3°outwardly and creates two equal spans of 150 m.The bridge was constructed by an unbalanced rotation construction method,by which the structure weighing 19600 t was swung 74°into position.During the construction process,the gravity center of the pylon was supposed to move outwardly,with the likelihood of overturning,additionally,the preliminary tensioning of stay cables would induce disconnection and torsional movement of steel girders.To address these issues,the bridge construction process was simulated in MIDAS Civil to work out control measures.As per the analysis,when fitted with sand cylinders and counterweighted,the anti-overturning coefficient of the pylon can be improved to 1.303,indicating that the pylon construction will be safe.Dismantling the scaffolds beneath the steel girders at the pylon root in advance and decreasing preliminary tension of stay cables is beneficial to the stability of the steel girders.The rotation process of the structure was under monitoring,with a rotating speed of 0.65(°)/min.The rotation construction was carried out smoothly,and after completion,the monitored geometry of the superstructure and stay cable forces met the code requirements.

关 键 词：斜拉桥 斜塔 曲线梁 转体施工 智能监测 施工控制 

分 类 号：U448.27[建筑科学—桥梁与隧道工程] U445.465[交通运输工程—道路与铁道工程] U445.1