摘要
充分利用振动测试得到的结构全局振动信息和构件局部振动信息,可以获得能够反映斜拉桥真实状况的有限元模型。本文以克拉玛依友谊大桥为例,首先利用环境激励振动试验得到的结构整体振动频率,结合该桥设计的初始有限元模型,运用基于动力特性的响应面法完成了该桥有限元模型的修正。然后利用振动测试中得到的斜拉索局部振动的频率,通过振动法常用的3种简化计算公式进行了相应斜拉索索力的计算,并与模型修正得到的结果进行了比较分析。得到如下结论:斜拉桥的索力大小往往影响着其动力反应有限元模型的准确性,为了便于区分实测振动数据中的全局振动和局部振动信息,对于双索面斜拉桥,索面内应至少在两根斜拉索上布设拾振器,且需测试面内和面外方向的振动;考虑垂度和弹性影响的索力计算公式可以相对简单且准确地计算索力的大小;局部振动计算得到的索力可以作为已知条件,对有限元模型进行再修正。
Taking full advantage of the global vibration information of structure and the local vibration information of the component obtained from the vibration test,a finite element model capable of reflecting the real condition of the cable-stayed bridge can be obtained.Taking the Friendship Bridge in Kelamayi as an example,this paper firstly modifies the finite element model of the bridge by using the global vibration frequency of structure excitation test and the initial finite element model of the bridge,and using the response surface method based on dynamic characteristics.Then,by using the frequency of local vibration of the stay cable obtained from the vibration test,the cable tension of the corresponding stay cable was calculated by three simplified formulas commonly used in the vibration method,and the results were compared with those obtained by the model modification.The following conclusions are obtained :the cable force of cable-stayed bridge often affects the accuracy of the dynamic response finite element model.In order to make it easy to distinguish the global vibration and local vibration information in the measured vibration data,for two-cable plane cable-stayed bridge,the vibration pickup should be arranged on at least two stay cables,and the vibration in plane and out of plane should be tested.The formula for calculating the cable force that takes into account the effects of sag and elasticity can calculate the cable force relatively easily and accurately.The cable force calculated by the local vibration can be used as a known condition to re-correct the finite element model.
作者
黄勇
乐威杰
车泽鑫
杨振宇
刘金龙
HUANG Yong;LE Weijie;CHE Zexin;YANG Zhenyu;LIU Jinlong(Key Laboratory of Earthquake Engineering and Engineering Vibration,Institute of Engineering Mechanics,CEA,Harbin 150080,China)
出处
《地震工程与工程振动》
CSCD
北大核心
2018年第5期67-76,共10页
Earthquake Engineering and Engineering Dynamics
基金
国家科技支撑计划项目(2015BAK17B05)
中央公益事业基本科研业务专项基金项目(2014A01
2016B06)
国家自然科学基金项目(51278471)
中国地震局创新团队发展计划~~
关键词
斜拉桥
有限元模型修正
子结构
振动测试
索力
cable-stayed bridge
model updating
substructure
vibration testing
cable tension
