超大跨斜拉桥索塔施工误差影响研究

Research on Influence of Construction Error on Pylon of Ultra-long Span Cable-stayed Bridge

现行规范中针对常规索塔制定的误差标准对于超高索塔可能不再适用。以苏通大桥为工程背景,采用有限元软件MIDAS建立该桥的空间有限元模型,对该桥在一系列的索塔纵向偏位以及高程误差的工况下进行了分析,对在这些工况下全桥的几何形态和结构受力的敏感性进行了研究,考察的内容包括索塔偏位和应力、主梁线形和应力以及斜拉索索力。得到了不同的误差组合对索塔结构位移及内力的影响规律,对确定超大跨斜拉桥索塔施工误差标准提出了建议。

The active error criterion for pylons of cable-stayed bridge with general height maybe not applicable for the pylons with extreme great height. Based on Sutong Bridge, a 3D FEM model of this bridge was built by using software MIDAS. Analysis of this bridge under several cases of pylon with different longitudinal deviations and altitude errors was carried out. The sensitivity of the geometry configuration and stress state of the whole bridge such as deviation and stress of the pylon, alignment and stress of girder, and cable force were investigated.The rules of displacement and inner force error of pylon structure caused by different error cases were summarized, and some suggestions were given for determining the error criterion for construction of ultra-span cable-stayed bridge.