WAVELET PACKET-BASED DAMAGE IDENTIFICATION FOR A THREE-DIMENSIONAL FRAME STRUCTURE

Some factors affecting damage identification results on the basis of wavelet packet, such as the choice of basis functions of the wavelet packet, the choice of decomposition levels of the wavelet packet and the choice of excitation force exerted on the structures are analyzed in detail. By applying the wavelet packet decomposition technique, sensitive parameters of energy curvature difference for damage identification are constructed. The numerical simulation of a three-dimensional frame structure with some damage cases is carried out. The experimental results indicate that superposition of the energy curvature difference of the first several wavelet packet component signals has a good capacity for damage identification even in the case of noise. Finally, some concluding remarks are given.