Crack identification in plates using wavelet analysis

• Published in: Journal of sound and vibration Vol. 270; no. 1; pp. 279 - 295
• Main Authors: Douka, E., Loutridis, S., Trochidis, A.
• Format: Journal Article
• Language: English
• Published: London Elsevier Ltd 06.02.2004; Elsevier
• Subjects: Exact sciences and technology; Fundamental areas of phenomenology (including applications); Physics; Solid mechanics; Structural and continuum mechanics; Vibration, mechanical wave, dynamic stability (aeroelasticity, vibration control...); Crack array; Defect characterization; Parallel configuration; Cracked plate; Wavelet transformation; Crack depth; System identification; Vibrational mode; Spatial variation; Edge crack
• ISSN: 0022-460X; 1095-8568
• DOI: 10.1016/S0022-460X(03)00536-4

In this paper, a method for crack identification in plates based on wavelet analysis is presented. The case of an all-over part-through crack parallel to one edge of the plate is considered. The vibration modes of the plate are analyzed using the continuous wavelet transform and both the location and depth of the crack are estimated. The position of the crack is determined by the sudden change in the spatial variation of the transformed displacement response. To estimate the depth of the crack, an intensity factor is defined which relates the depth of the crack to the coefficients of the wavelet transform. An intensity factor law is established which allows accurate prediction of crack depth. The viability of the proposed approach is demonstrated using simulation examples. In view of the obtained results, the advantages and limitations of the proposed approach as well as suggestions for future work are presented and discussed.