Damage characterization in plates using singularity of scale mode shapes

Abstract

Damage is a prevailing physical phenomenon in in-service structures; accumulation of damage can cause catastrophic structural failure. For damage identification in plates, the concept of scale mode shape with fractal singularity is formulated based on 2D Gabor wavelet transform incorporating fractal dimension analysis of measured mode shapes. With this concept, a scale fractal complexity spectrum is created to reveal mode shape singularities by eliminating noise and interference. The singularity manifests the abnormality of the mode shape, clearly indicating damage. This study develops a philosophy of fusing wavelets and fractals to detect singularities of physical fields in noisy conditions.