北京机场南线收费站索膜体系预张力的实现

Procedure of Tensioning the Cable-membrane System of the Toll Station on the South Line Towards Beijing Airport

北京机场南线收费站工程施工的重点及难点是钢索体系的安装以及体系预张力的形成。按照安装顺序,对吊索安装、下拉索张拉、边环索张拉、谷索张拉4个状态进行了精确的施工模拟验算,作为张拉设备选择、测量监控和应力监测的依据,实际施工过程完全验证了施工模拟计算的准确性。整个索膜体系安装共分11个步骤,有条不紊地将如此复杂的大跨度柔性空间结构体系准确施加上预应力设计值,总结了其中值得参考的施工经验。

The difficulties lying in the project of the great pavilion on the south line towards Beijing Airport are installing and tensioning the cable system.Accurate construction simulation is carried out according to installation sequence such as installing suspension cables,tensioning guy cables,stretching side ring cables,and tensioning valley cables,in order to check if tensioning equipments are appropriate,and make it to be the basis of measure supervision.The results in the actual construction completely verify the accuracy of simulation.The whole process of cable system installation is divided into 11 steps,which ensure applying prestress on the complicated big span flexible space structure.This paper summarizes the experience acquired during the construction.