几何非线性效应下的CFRP索斜拉桥动力特性

CFRP cable-stayed bridge's dynamic properties with geometric nonlinear effect considered

为研究CFRP索斜拉桥与钢索斜拉桥的静动力特性的区别,分别讨论以南京长江三桥为原型的跨径为648m的CFRP索斜拉桥和钢索斜拉桥,采用有限元法对比分析了考虑几何非线性效应的CFRP索及钢索斜拉桥的主要静动力性能,并对比分析了垂度效应、大变形及梁-柱效应对这2种斜拉桥的静动力性能的影响。最后分析了不同的结构体系、辅助墩设置个数等参数对CFRP索斜拉桥的动力特性的影响。研究结果表明:垂度效应对CFRP索斜拉桥的静动力性能影响较小,对钢索斜拉桥静动力性能影响显著;大变形及梁-柱效应对2种斜拉桥的静动力性能影响较大,计算时不可忽略该效应;所得结论可为长大跨斜拉桥的分析计算提供一定的参考。

To study the difference of static and dynamic properties between CFRP cable-stayed bridges and steel cable-stayed bridges, the finite element method was used to analyze the CFRP cable-stayed bridge and steel cable-stayed bridge＇s static and dynamic properties with geometric nonlinear effect considered. With the third Nanjing Yangtze River Bridge with a span of 648 m as the prototype the influences of sag effect, large deformation effect and beam-column effect on two kinds of cable-stayed bridges＇ static and dynamic performance were compared. Different systems of structure and different numbers of auxiliary piers＇ influence on CFRP cable-stayed bridge＇s dynamic properties were analyzed. The results show that the influence of sag effect on CFRP ca- ble-stayed bridge＇ s static and dynamic performance is small, but appreciable on steel cable-stayed bridge; the influences of large deformation effect and beam-column effect on these two kinds of cable-stayed bridges＇ static and dynamic properties are relatively bigger and these effects cannot be ignored in calculation; these conclusions can provide references for long span cable-stayed bridges＇ analysis. 5 tabs, 4 figs, 12 refs.