Damage detection of beam-structure using wavelet transform

The present paper focuses on the identification of crack in a beam structure using wavelet transform (WT) that could be considered of primary importance in a diagnosing process. The theoretical background of the method is wavelet transform can provide the regional property of the signal. In this paper, the wavelet transform is applied to the spatial-frequency analysis of the strain-signal of the cracked cantilever beam. The location of the crack in the beam can be calculated by wavelet transform. It is shown how the possibility to efficiently identify localized damages. The Simulation results illustrate that the crack position can be detected exactly by both haar wavelet and db3 wavelet transform of the strain information in spatial domain. It can be seen that the high frequency signals indicate the information of the location of the crack through the multi-lever decomposition. As far as locating damage, haar wavelet is superior to db3 wavelet. This method can be applied to health monitoring of the structure on line.