独塔混合梁斜拉桥施工控制技术研究

Research on construction control technology of single-pylon hybrid girder cable-stayed bridge

八尺门大桥主桥为主跨200m的独塔单索面混合梁斜拉桥,该桥钢箱梁采用悬臂拼装施工,边跨预应力混凝土箱梁采用支架现浇法施工。施工控制中,基于无应力状态法,采用MIDAS Civil软件建立有限元模型,分析了合理成桥状态计算、合理施工状态计算、桥塔结构监控计算、钢箱梁制造线性计算及斜拉索无应力索长等关键技术。桥塔、主梁和斜拉索的施工控制结果表明:实测值与理论值均吻合较好,误差在合理范围内,满足设计要求,成桥状态良好。

The main bridge of Bachimen Bridge is single-pylon and sigle-cable-plane hybrid girder cable-stayed bridge with a main span of 200 m. The steel box girder of the bridge is constructed by cantilever erection,and the side span prestressed concrete box girder is constructed by cast-in-situ support. In the construction control,based on"un-stressed state method",the software MIDAS Civil is used to establish the finite element model,and the key technologies such as the reasonable bridge state calculation,the reasonable construction state calculation,the pylon monitoring and calculation,the manufacturing alignment calculation of steel box girder and the non-stress cable length of the cable-stayed cable are analyzed. The construction control results of pylon,girder and cable-stayed cable show that all the measured values match well with the theoretical values,the errors are all within the rational ranges and the completed bridge can meet the design requirement s and is in good condition.