Damage detection of structures by wavelet analysis

Over the last few decades, the damage identification methods of civil and mechanical structures have been drawing much interest from various fields. Wavelet analysis, a relatively new mathematical and signal processing tool, is one of such methods that has been studied recently. It is a time–frequency analysis that provides more detailed information about non-stationary signals which traditional Fourier analysis miss. This rather new method has been applied to various fields including civil, mechanical and aerospace engineering, especially for damage detection and structural health monitoring (SHM). The purpose of this paper is to provide the review of the research that has been conducted on damage detection by wavelet analysis. First, the theory of wavelet analysis is presented including continuous and discrete wavelet transform followed by its application to SHM. Then more specific applications—namely crack detection of a beam and mechanical gear and roller damage—are presented.