对系杆拱桥刚性吊杆更换的思考

Thinking About Rigid Hanger Replacement of the Tied Arch Bridge

因无法利用振动法测试刚性吊杆索力,给吊杆更换设计带来一定不确定性。本次通过仿真计算和现场千斤顶张拉综合判定吊杆成桥索力。根据目标索力,按照分批张拉和等效转移原则,利用临时吊杆系统逐根、交叉更换全桥吊杆,取得良好效果。本桥采用钢绞线整束挤压拉索体系吊杆可以极大提高吊杆耐久性,由于挤压钢绞线索体锚头面积较小,不需要调整原先钢丝镦头锚锚端尺寸,给施工带来方便。

Due to rigid hanger,it is difficult to get cable force by vibration method.Here we use the simulation calculation and jack tension synthetically to get final constant hanger internal force.Then by batch tensioning and equivalent method,we replace successfully all the hanger through help of the temporary suspender system one by one.Furthermore, the steel strand bundle of extruded cables can sovle effectively small size of the hanger anchor head and improve evidently hanger durability .