斜拉-悬吊体系管桥换索与调索分析

Analysis of Cable Replacement and Cable Force Adjustment for the Cable-stayed Suspension Pipe Bridge

结合某斜拉-悬吊体系管桥换索监测与索力调整的工程实践,在分析换索后全桥结构性能的基础上,阐述管桥索力调整的原则与方法。结合平面杆系有限元模型和索力调整的矩阵方法,采用试算法确定索力调整方案,并监测、分析换索后的管道应力、变形及斜拉索索力。结果表明:对于斜拉-悬吊体系管桥类非线性的超柔性结构,考虑结构大变形的非线性影响,有限元模拟、索力测量和调整等方法具有工程实用性,且调索应以使全桥结构受力更趋合理为目的,调索后管道的线形变化符合要求,换索施工前管桥不合理的受力状态及管道异常线形得到改变。

The research expounds the principle and method of cable force adjustment with analysing the whole bridge structure performance after cable replacement on a engineering project of cable-stayed suspension pipe bridge.Combining the finite element model of plane truss and practical method for mutual influence matrix of cable force adjustment,the trial and error method is adopted to determine the cable force adjustment scheme,and the pipe stress,deformation and cable force of cable after cable replacement are monitored and analyzed.The results show that it is reasonable and appropriate for the nonlinear super-flexible structure such as cable-stayed and suspension system pipe bridge through finite element simulation,cable force measurement and adjustment method considering nonlinear effect of large deformation of structure.The purpose of cable adjustment is to maintain the stress of the whole bridge structure more reasonable.The linear change of the pipeline after adjustment meets the requirements,and obviously changes the unreasonable stress state of pipe bridge and abnormal pipeline alignment before cable replacement.