IMPROVED DAMAGE IDENTIFICATION FROM MODAL STRAIN ENERGY CHANGE USING HIGH-ORDER MODAL PERTURBATION AND MODES DIVISION METHOD
An improved structural damage identification method based on modal strain energy change before and after damage is developed in this paper. The damage localization method from modal strain energy change is briefly outlined. The structural perturbation considering high-order terms are given to obtain the change in the mode shape before and after damage in the structure. Modal terms required in the computation are divided into higher terms and lower terms by using series expansion. The higher terms are expressed in terms of sum of infinite series of the lower parameters. The damage quantification approach based on second-order modal perturbation and modes division method is derived. The damage coefficient of each structural element is obtained by solving the second-order nonlinear matrix equations. Numerical example with a cantilever beam is used to illustrate the performance and robustness of the proposed method. Simulation results show that the improved method gives less truncation errors with a more rapid convergence and more accurate results than any others when only a few number of lower modes of the system is used in the damage quantification. When the structural parameters change a lot, it can also give more accurate results even only the first few terms are used in series expansion.
modal strain energy damage detection second-order perturbation modes division method
Qin-Xiang He Zhi-Chun Yang Lei Zu
School of Aeronautics, Northwestern Polytechnical University, Xian 710072, P.R.China School of Aeronautics, Northwestern Polytechnical University, Xian 710072, P.R. China School of Science, Xian University of Technology, Xian 710054, P.R. China
国际会议
长沙
英文
419-425
2007-11-19（万方平台首次上网日期，不代表论文的发表时间）