摘要
为评估某钢筋混凝土渡槽一空腹桁架拱的现役状态,在静力检测的同时对其进行环境振动测试,采用特征系统实现算法识别模态参数,结果表明其实测动力特性与初始有限元模型分析结果之间存在明显的差异.因此,采用基于灵敏度分析的有限元模型修正技术,选择测量精度较高的实测模态频率作为修正基准,选取各构件的弹性模量和密度作为修正参数,对该桁架拱的有限元模型进行修正.修正结果表明,修正后的有限元模型能更好地反映结构的动力特性,可作为该结构状态评估的基准有限元模型.
In order to assess in-service condition of an arched Vierendeel truss of RC aqueduct, ambient vibration test was conducted together with its static test, and modal parameters were identified with eigensystem realization algorithm. Comparison with the result from initial finite element analysis indicated that there was distinct difference between identified and simulated modal parameters. Thus, the identified frequencies with higher accuracy were selected as updating benchmark, and the elastic module and densities of truss components were selected as updating parameters, the finite element model of this truss was updated based on sensitivity analysis. The result showed that the updated finite element model could properly reflect the dynamic characteristics of the arched Vierendeel truss and it could serve as a baseline finite element model to assess the structural condition.
出处
《兰州理工大学学报》
CAS
北大核心
2009年第5期122-125,共4页
Journal of Lanzhou University of Technology
基金
甘肃省科技攻关项目(2GS057-A52-008)
关键词
渡槽
有限单元法
环境振动测试
模型修正
灵敏度分析
aqueduct
finite element method
ambient vibration test
model updating
sensitivity analysis
