斜拉桥模态试验研究

Experimental Modal Analysis of Cable-stayed Bridge

对斜拉桥进行试验模态分析,对验证设计、建立结构的动力学模型以及桥梁安全运行状态进行评估。采用环境脉动法对仙桃汉江公路大桥进行模态试验分析,取得了该斜拉桥振动的较为正确的模态频率、阻尼及较理想振型,与有限元计算结果基本吻合,从而验证了该模态分析方法的合理性和有限元模型的准确性,也为大桥的进一步研究提供依据。使得大桥长期安全运行的健康监测评估得到实现。

Because of the rapid development of construction of large-scale bridges with flexible girder, it is of high significance to verify the design scheme, establish dynamical model and evaluate the security condition by experimental modal analysis. This paper has analyzed the modal parameters of Xiantao Hanjiang River Road Bridge by the ambient vibration measurement. The experimental modal frequencies, damping ratios and vibration mode shapes are basically in good accordance with the analytical results by finite element method, showing the rationality of this modal experimental method and the accuracy of this finite element model and providing basis for further research of the bridge.