Applications of wavelet transforms to damage detection in frame structures

This paper presents applications of the wavelet transform to detect cracks in frame structures, such as beams and plane frames. A simplified review of the theory behind the wavelet transform is given, and the ability of wavelets to detect crack-like damage in structures is demonstrated by means of several numerical examples. The method requires the knowledge of only the response of the damaged structure, i.e. no information about the original undamaged structure is required. In addition, it is shown that the procedure can detect the localization of the crack by using a response signal from static or dynamic loads. Moreover, the response needs to be obtained only at the regions where it is suspected that the damage may be present. The results of the simulation show that if a suitable wavelet is selected, the method is capable to extract damage information from the response signal in a simple, robust and reliable way. (C) 2003 Elsevier Ltd. All rights reserved.