多跨长联公轨合建钢桁梁桥顶推施工控制技术研究

Research on Incremental Launching Construction Control Technology of Multi-span Long-connected Highway Track Co-construction Steel Truss Bridge

杭甬高速钱塘江大桥结构形式采用悬链形上加劲连续钢桁梁桥,跨径组合为73.4 m+122m+4×240 m+122m+73.4m,全长1350.8 m.上部结构主桁分别采用步履式顶推和拖拉式顶推方法从两侧向中跨施工,最后跨中直接合龙.为使该桥建成后线形及应力均达到设计目标,基于钱塘江大桥钢桁梁的工程特点和施工方法,结合有限元计算结果,确定了本桥的施工控制工作内容.施工控制结果表明:整个顶推施工过程中,本桥主桁线形、结构的应力状态均控制在规范限值以内,与理论值偏差较小,达到了施工监控目标.

The structure of Qiantang River Bridge in Hangzhou-Ningbo Expressway is a catenary stiffened continuous steel truss bridge. Its span combination is 73.4 m + 122 m + 4 × 240 m + 122 m +73.4 m. Its total length is 1 350.8 m. The main truss of the superstructure is constructed from both sides to the middle span by using the walking incremental launching method and the dragging incremental launching method, respectively, and finally is closed directly at the middle span. In order to make the alignment and stress of the finished bridge reach the design goal, the construction control content of the bridge is determined according to the engineering characteristics and construction method of the steel truss girder of Qiantang River Bridge, and combined with the result of finite element calculation. The construction control results show that during the whole jacking construction process, the stress states of the main truss alignment and structure of the bridge are controlled within the specification limits, and the deviation from the theoretical value is small. The construction monitoring target is achieved.