基于环境激励的ERA方法在网架结构振动测试中的应用研究

Eigen-system realization algorithm used in the modal parameter identification of spacial trusses based on ambient excitation

基于环境激励的结构振动测试的方法中ERA方法是重要的时域分析方法。本文主要是以随机减量法(RD)和NExT两种数据处理方法结合ERA算法,对绥化学院正在建的网架结构的基本模态参数进行测试。通过分析比较得出RD/ERA和NExT/ERA较直接ERA有更高的精度,且实测分析结果与有限元分析结果较吻合。为网架结构在环境激励下用ERA方法测试模态参数提供了实验依据。

Eigen-system realization algorithm is an important time domain method for structural modal parameter identification based on the ambient excitation. The outhors carry out the modal analysis and modal test for the spa- cial truss of Suihua University by using random decrement technique or natural excitation technique for data pro- cessing, then input the eigen-system realization algorithm for solving the modal parameters of the spacial truss. Com- parisons by analysis show that RD/ERA and NExT/ERA have higher accuracy than the direct ERA, and the analy- sis results meet the finite element method results well. This paper provides an experimental basis for using ERA to test the modal parameters of the spacial trusses.