Kurtosis analysis for crack detection in thin isotropic rectangular plates

This paper presents a crack identification technique in plate structures based on kurtosis analysis. Simulated vibration modes generated from a simply supported thin isotropic rectangular plate containing a crack parallel to one of its edges of arbitrary length, depth and location are subjected to kurtosis analysis. Both the location and length of the crack are accurately determined by the abrupt change in the spatial variation of the derived kurtosis signal. The dependence of both the maximum value and energy of the estimated kurtosis on crack depth provides a quantitative estimation of crack depth. Simulation examples for plates with cracks of varying depth at different positions are utilised to demonstrate the effectiveness of the proposed approach. The effect of added noise on the estimation accuracy of the method was systematically investigated using a noise stress test. The ability of the proposed method to accurately identify the location, length and depth of cracks despite the presence of noise and its computational simplicity makes it attractive for practical applications.