（上海大学土木工程系，上海 200072）

［摘要］介绍了对一座钢结构人行桥进行的全桥动力测试，并对结构的动力特性进行了分析。利用有限元计算软件进行了结构模态分析，通过参数分析找到了各参数与结构振动频率之间的关系。基于这一关系以及实际动力测试结果，通过对有限元模型参数进行一系列修正，建立起可用于该结构加固改造前后状态评估的基准有限元模型。该方法以及参数分析后得到的相关结论可为类似结构的设计与加固改造提供借鉴。

［关键词］人行桥；动力特性；动力测试；模态分析

Analysis on dynamic characteristics of an existing steel footbridge

Li Dong，Fa Yongsheng

(Civil Engineering Department, Shanghai University, Shanghai 200072, China)

Abstract:The dynamic testing on an existing steel structure footbridge is introduced, and the dynamic characteristics are analyzed. Then modal analysis is performed by using finite element method. In this way, the relations between parameters and structural vibration frequency are figured out by parameter analysis. The FE model is calibrated based on the results of dynamic testing and parameter analysis, furthermore, the baseline FE model is constructed. This calibrated FE model can be used in the conduction evaluation before and after the structural strengthening. This method and the conclusion from the parameter analysis will be reference to similar problems.

Keywords:footbridge; dynamic characteristics; dynamic testing; modal analysis