Damage Detection Method for Composite Structures Based on a Combined Technique of Cross Modal Strain Energy and Niche Genetic Algorithms

Abstract

This paper presents an effective method for structural damage detection using the combined technique of the up-to-date cross modal strain energy (CMSE) and niche genetic algorithms (GAs). The traditional modal strain energy method is not convenient for structural damage detection because it needs to compare the modal information between the same modes of the baseline and damaged structures, and also requires the analytical and measured modes to be consistent in scale, or to be normalized, but no such constraint is required for the CMSE method. However, the current CMSE method is still deficient because it cannot effectively determine the locations of structural damage. In order to overcome the shortcoming of the CMSE method in structural damage detection, a combined method of the CMSE with the niche GAs is proposed in this paper to enhance the capability of identifying structural damage location. Numerical studies of damage detection for the case of a model of an airfoil of composite material are given, and the obtained results show that the method proposed in this paper is successful to detect the damage of complex structures.