摘要
根据平行索面悬索桥的结构体系特征,可以将其划分为几个相对独立的子结构。充分利用振动测试得到的子结构局部振动信息和结构整体振动信息,可以分阶段进行有限元模型修正,从而提高优化效率。本文以克拉玛依市龙门桥为例,结合该桥设计的有限元模型和环境激励振动试验结果,进行了整桥模型修正和子结构多阶段模型修正。首先通过振动法计算得到边悬索的索力近似替代主缆索力,将其施加在整桥有限元模型中,运用基于动力特性的响应面法完成传统的模型修正,得到修正后的土-结构相互作用的弹簧刚度系数和吊杆索力;其次利用主塔横向模态相对独立的特点,通过对主塔子结构模型的修正得到合理的弹性支承参数;再将其施加在初始的整体有限元模型中,完成该桥的子结构分阶段有限元模型修正;最后比较子结构多阶段模型修正与传统整桥模型修正方法的效果,可以看出相比传统模型修正,所提方法不仅提高了修正精度,而且大幅度提高了优化效率。
According to the structural characteristics of the parallel cable-plane suspension bridge, it can be divided into several relatively independent substructures. Taking full advantage of global vibration information of structures and local vibration information of substructures obtained from vibration tests, a finite element model parameter of reflecting the real condition of suspension bridges can be obtained one by one. Taking the Longmen Bridge in Karamay as an example, the finite element model of the bridge and the test results of the environmental excitation vibration are used in this paper to carry out the multi-stage finite element method. Firstly, the cable force of side suspension cable is calculated to replace the main cable force approximately by the vibration method, it is applied to the overall finite element model, and the response surface method based on dynamic characteristics is used to complete the finite element model revision of the bridge, the elastic support parameters of the soil-structure interaction under the main pylon platform and derrick cable forces are obtained through the modification of the main tower structural model. Then, the elastic support parameters of the soil-structure interaction under the main pylon platform are obtained through the modification of the main tower structural model by using the relatively independent transverse mode of the main pylon. The reasonable elastic-soil-structure interaction parameters of the main tower are applied to the overall finite element model again, and the response surface method based on dynamic characteristics is used to complete the finite element model revision of the bridge. Finally, comparing the effect of substructure multi-stage model updating with traditional model updating method, we can see that the proposed method not only improves the accuracy of updating, but also greatly improves the efficiency of optimization.
作者
车泽鑫
黄勇
杨振宇
刘金龙
CHE Zexin;HUANG Yong;YANG Zhenyu;LIU Jinlong(Institute of Engineering Mechanics, China Earthquake Administration, Harbin 150080, China;Key Laboratory of Earthquake Engineering and Engineering Vibration of China Earthquake Administration, Harbin 150080, China)
出处
《地震工程与工程振动》
CSCD
北大核心
2019年第2期213-224,共12页
Earthquake Engineering and Engineering Dynamics
基金
中国地震局工程力学研究所基本科研业务费专项资助项目(2018QJGJ06)
国家科技支撑计划项目(2015BAK17B04-3)
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
悬索桥
有限元模型修正
子结构
振动测试
索力
suspension bridge
model updating
substructure
vibration testing
cable force
