千米级斜拉桥的动力几何非线性分析  

Dynamic nonlinear analysis of cable-stayed bridges of kilometers length

作　　者：韩振峰[1] 叶爱君[1] 范立础[1] 

机构地区：[1]同济大学土木工程防灾国家重点实验室,上海200092

出　　处：《土木工程学报》2010年第6期67-73,共7页China Civil Engineering Journal

基　　金：国家科技支撑计划项目(2006BAG04B00)

摘　　要：对于千米级的超大跨度斜拉桥,几何非线性因素对上部桥跨结构的抗震性能的影响规律迄今为止还没有得到很好的研究。为此目的建立了两个千米级斜拉桥模型,首先分析恒载几何刚度对超大跨度斜拉桥动力特性的影响;然后在成桥状态下进行动力时程分析,考虑几何非线性,分析几何非线性对千米级斜拉桥的地震反应特性的影响;最后对两个模型的计算结果进行比较并得到规律。实例分析表明,在进行上部桥跨结构的抗震动力分析中,非线性因素——主要是几何非线性,对千米级跨度斜拉桥的抗震性能影响随着跨径的增大是比较显著的。在未来建造1600m以上的超大跨度斜拉桥时,动力几何非线性将会是一个专门的抗震研究课题,应进行细致的抗震分析与设计。For long-span cable-stayed bridges （CSBs） longer than one kilometer, the response characteristics of the superstructure caused by the nonlinear factors under earthquakes have not been adequately studied. Two models of CSBs longer than 1 km were set up to analyze the dynamic properties due to the dead load geometry stiffness, to conduct dynamic time-history analysis through considering the geometry nonlinearity at the final construction stage, to obtain the response characteristics under earthquake, and to compare the results of the two models. The results show that the nonlinear （mainly geometry nonlinear） effects cannot be ignored in dynamic analysis of the superstructure, and the effects for the seismic performance of the CSBs increase significantly with increase of the span. The dynamic geometric nonlinearity poses a special problem for seismic resistance, and should be analyzed and designed carefully for CSBs over 1600 meters.

关 键 词：斜拉桥 动力 几何非线性 

分 类 号：U448.27[建筑科学—桥梁与隧道工程]