A two-stage method to detect damages in aluminum plates using curvature modal shape subtraction indicator and particle swarm optimization

Abstract

A two-stage method is proposed for effectively identifying damages in aluminum plates. The first stage focuses on detecting damage locations using the curvature modal shape subtraction indicator to reveal the singularities, i.e., subtract the curve modal fitting shape from the curvature modal shape. Then in the second stage, particle swarm optimization (PSO) is employed to search the damage severities from the pre-calculated damage evaluation database (relationship between the natural frequencies and severities). Simulations and experimental signals are performed using finite element method (FEM) and experimental modal analysis (EMA) respectively to detect multiple damages in a cantilever supported aluminum plate. The results show that the effectiveness of the two-stage method to detect multiple damages in aluminum plates with reasonable precision.