高耸柔性结构的模态参数识别及模型修正研究

Modal parameter identification and model updating of high-rise flexible structure

采用三种基于环境激励的模态参数识别方法(多参考点稳定图算法(M-NExT/ERA)、数据驱动随机子空间识别法(SSI/Data)和增强频域分解法(EFDD))对广州新电视塔(GNTVT)进行模态参数识别,得到前12阶模态参数。利用有限元软件ANSYS建立GNTVT的有限元模型,根据识别得到的实测模态参数,结合遗传算法对GNTVT有限元模型进行修正。结果表明:识别方法可靠,得到的结果具有较好的精度;修正方法前5阶模态具有较好效果,满足工程需要。

Three different modal identification methods based on ambient vibration( multiple reference DOFs stabilization diagram algorithm( M-NExT / ERA),data-driven stochastic subspace identification( SSI / Data) and enhanced frequency domain fecomposition( EFDD)) were applied to the modal parameters identifacation of the Guangzhou New TV Tower( GNTVT). Then finite element analysis model of GNTVT was modeled using ANSYS,and the identified modal parameters results were used for the model updating based on genetic algorithm of GNTVT FEA model. The results indicate that the modal identification methods used in the paper are reliable,since the identified modal parameters has acceptable accuracy; the model updating method based on genetic algorithm has better effect on the first five modes,and can satisfy the engineering demand.