大跨度斜拉索参数振动研究  

Research on Parametric Oscillation of Super Long Cables

作　　者：徐明骁[1] 葛耀君[1] 马婷婷[1] 赵林[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：《科学技术与工程》2011年第19期4509-4515,共7页Science Technology and Engineering

基　　金：国家自然科学基金项目(90715039;50978203和51021140005);科技部国家重点实验室基础研究项目(SLDRCE08-C-02)联合资助

摘　　要：针对大跨度斜拉桥拉索的参数振动问题,利用三主梁建立模型的有限元方法计算三塔斜拉桥动力特性,并计算单根拉索动力特性。通过频率比较得出易于发生参数振动的拉索。取两个典型长索进行分析,通过有限元和数值积分两种方法比较讨论各种因素(激励频率、激励振幅、阻尼)对索参数振动的影响。结果表明:当索频率和全桥频率成一定比率时,极易发生大幅度参数振动,对桥梁的使用和安全有不利影响。In order to consider the parametric oscillation of the cables of super long cable-stayed bridges,triple-girder finite element model is built to obtain the global modes.Also,the modes of the cables are calculated and by comparing the cables in which parametric oscillation may occur are found out.Take the examples of two typical cables,two methods including finite element method and numerical integration are used to analyze the influences of various factors（frequency and amplitude of the excitation,damper）.Results show that parametric oscillation will be very likely to happen when the frequencies of the cables is proportional to the global frequencies,which can do harm to the security and durability of the bridges.

关 键 词：斜拉桥 拉索 参数振动 有限元 数值积分 

分 类 号：U448.27[建筑科学—桥梁与隧道工程] U441[交通运输工程—道路与铁道工程]