Eigenvalue Perturbation Theory with Applications to Small Structural Damage Detection
Yu Long,Jiang Jiesheng,Yan Yunju,Liu Qin
(School of Science, Northwest Polynomial University, Xi'an 710072, China)

Abstract: 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 mod el of damaged structure is an important is sue. Adopting the advanced modeling me thod 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 computat ion 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 comput ational tack is greatly reduced.
Keywords: eigenvalue perturbation theory, dynamic damage detection, finite elament mlodel.