特征值摄动法在利用动响应结构小损伤检测中的应用

目前在使用遗传算法或神经网络方法进行结构动力学损伤检测,需要基于少量的在线测量损伤结构数据和大量的数值仿真数据来实现,其中通过有限元方法来获得仿真数据的巨大计算量是动力学结构损伤检测方法发展中所面临的一个重要问题。本文在建模方面应用近年来提出的调整单元刚度模拟损伤的先进方法,以保证在损伤前后结构自由度数目不变;在此基础上应用特征值摄动法来减少损伤检测中计算量,并通过对复合材料层合板响应信号的小波分析验证了使用一阶矩阵摄动在有效降低计算量的同时,可以获得对损伤检测而言足够准确的响应信号。

Eigenvalue Perturbation Theory with Applications to Small Structural Damage Detection

Current methods for structural damage identification,such as GA algorithms and neural networks technology,are implemented often based on a few measured data and large numbers of simulation data.The tremendous time-consuming computational work for calculating the response data to establish the dynamic model of damaged structure is an important issue.Adopting the advanced modeling method of element stiffness matrix modification,the order of the structure stiffness matrix can be kept invariable in establishing the model of intact and damaged structures,and the eigenvalue perturbation theory is introduced to obtain the eigenvalues and eigenvectors of the damaged structure for reducing the computation load.The response signal of composite laminated plate by the wavelet transform,shows that the first order eigenvalue perturbation theory provides enough accurate dynamic response for detecting small structural damage while the computational tack is greatly reduced.