Damage Identification Research of Multi-Damage Plate Structures Based on the Discrete Wavelet Transform

This paper introduces the principle of wavelet transform and the 2D (two dimension) discrete wavelet transform method. Identification of damage location and estimation of damage degree are performed mainly. Modal nodes displacement data of the plate was decomposed using the two dimension discrete wavelet method to obtain the high frequency signal information of the damage location, revealing singular points of mode, so the damage locations are determined. The estimation of the damage degree is involved to different position and different damage depth of plate, and the quantity estimation of damage degree is achieved by the change of the maximize value of wavelet coefficients in many cases. The finite element simulation examples combine with the MATLAB results verification show that the proposed method is valid for the identification of damage location and estimation of damage severity of plate with multi-damage.