120 m跨钢-混组合连续梁桥施工方案研究  

Research on Construction Schemes of Continuous Steel-Concrete Composite Girder Bridge with a Main Span of 120 m

作　　者：岳秀鹏 孟姣 张文亮 庄亮东 王宏博 YUE Xiu-peng;MENG Jiao;ZHANG Wen-liang;ZHUANG Liang-dong;WANG Hong-bo(Shandong Hi-Speed Infrastructure Construction Co.,Ltd.,Jinan 250101,China;Department of Civil Engineering,Tsinghua University,Beijing 100084,China;Shandong Provincial Communications Planning and Design Institute Group Co.,Ltd.,Jinan 250101,China)

机构地区：[1]山东高速基础设施建设有限公司,山东济南250101 [2]清华大学土木工程系,北京100084 [3]山东省交通规划设计院集团有限公司,山东济南250101

出　　处：《世界桥梁》2023年第1期58-63,共6页World Bridges

基　　金：优秀青年科学基金项目(52022045);中国铁路总公司重大课题项目(K2019G004)。

摘　　要：长深高速高青—广饶段小清河特大桥主桥为主跨120 m的钢-混组合连续梁桥。结合该桥施工环境特点以及吊装法、顶推法和悬拼法的适用性,提出采用边跨分节段吊装、中跨悬拼的施工方案。为选择合理的悬拼方案,采用MIDAS Civil软件建立该桥空间杆系有限元模型,对比无支撑悬拼、扣索悬拼与钢桁架辅助悬拼3种悬拼方案的桥梁跨中挠度、应力和材料用量,选择施工速度最快、材料成本最低的无支撑悬拼方案。对无支撑悬拼方案的底板混凝土厚度及铺设长度2个关键设计参数的取值进行了分析,得出底板混凝土厚度取300 mm、铺设长度取9 m时,可有效提升结构整体刚度,减少跨中挠度,保证合龙精度,降低钢梁底板应力。The Xiaoqinghe River Bridge that carries the Gaoqing-Guangrao Section of the Changchun-Shenzhen Expressway is a continuous steel-concrete composite girder bridge with a man span of 120 m.By comprehensive consideration of the construction environments of the bridge and the applicability of three different construction methods,including the hoisting method,incremental launching method and cantilever assembly method,a plan to construct the side span using segment-hoisting method and the intermediate span by cantilever assembly method was proposed.A spatial link-element numerical model of the bridge was developed in MIDAS Civil to compare the efficiencies of three cantilever assembly methods,including the scaffolds-free cantilever assembly,cable-stayed cantilever assembly and steel-truss-assisted cantilever assembly,with focuses on the midspan deflection,stresses and material consumption.The scaffolds-free assembly method was finally selected,as it was a superior option in terms of construction schedule and material costs.The two key parameters,namely the thickness and placing lengths of the bottom concrete in the scaffolds-free construction plan,were analyzed,and the values of 300 mm for bottom concrete thickness and 9 m for placing lengths were determined.The utilization of appropriate parameters can improve the overall structural stiffness of the structure,reduce midspan deflection,ensure the closure accuracy and decrease the stresses in bottom plates of steel girders.

关 键 词：钢-混组合梁桥 施工方案 悬拼施工 底板混凝土 应力 竖向刚度 有限元法 

分 类 号：U448.216[建筑科学—桥梁与隧道工程] U445.46[交通运输工程—道路与铁道工程]