NONLINEAR FRACTURE SIGNAL ANALYSIS USING MULTIFRACTAL APPROACH COMBINED WITH WAVELETS
Djedjiga Ait Aouit, Abdeldjalil Ouahabi · Fractals · 2011
Based on the continuous Wavelet Transform Modulus Maxima method (WTMM), a multifractal analysis was introduced to discriminate the irregular fracture signals of materials. This method provides an efficient numerical technique to characterize statistically the local regularity of fractures. The results obtained by this nonlinear analysis suggest that multifractal parameters such as the capacity dimension D0, the average singularity strength α0, the aperture of the left side (α0 - α min ) and the total width (α max - α min ) of the D(α) spectra allow a better fit for the characterization of the different fracture stages. Discriminating the three principal stages of the fracture namely the fracture initiation, the fracture propagation and the final rupture, provides a powerful diagnostic tool to identify the crack initiation site, and thus delineates the causes of the cracking of the material.