武东特大桥施工监控

Construction Monitoring and Control of Wudong Bridge

武东特大桥主桥为(63+115+63)m变截面预应力混凝土刚构-连续组合梁桥,位于R=1 000 m的平面圆曲线上。采用有限元软件计算结构线形和内力,比较该桥型与连续梁桥、连续刚构桥的受力特点,分析曲率对该桥的影响程度;在施工阶段对结构线形和应力进行测试,并将实测结果与计算结果进行对比。结果表明:该桥受力与连续梁桥和连续刚构桥基本相同,且弯曲效应并不明显,可以近似按直线连续刚构桥的要求进行施工控制;悬臂施工过程中,混凝土容重对线形有较大影响,温度对节段标高的影响也较明显,应该适时修正材料参数;实测主梁线形和内力与计算值吻合较好,且均满足相关要求。

The main bridge of Wudong Bridge is a prestressed concrete rigid-frame and continuous girder hybrid bridge with variable cross section and having span arrangement（63＋115＋63） m and the bridge is located on a plan circular curve of R=1 000 m.The geometric shape and internal force of the bridge structure were calculated by the finite element software,the mechanical characteristics of the bridge were compared with those of the continuous girder and continuous rigid-frame bridges and the influential degree of curvature on the bridge was analyzed.In the construction stage of the bridge,the geometric shape and stress were measured and the measurements were compared with the calculations.The results indicate that the mechanical behavior of the bridge is basically similar to that of the continuous girder and continuous rigid-frame bridges,the curving effect of the bridge is not obvious and the construction control can be carried out approximately in accordance with the requirements for the straight continuous rigid-frame bridges.In the process of the cantilever construction of the bridge,the unit weight of concrete has considerable influence on the geometric shape and the influence of temperatures on the segment elevation is also significant and therefore,the parameters of materials should be modified timely.The measurements of the geometric shape and internal force of the main girder are agreeable with the calculation values and both the measurements and calculation values can meet the relevant requirements.