Numerical Analysis on Damage-induced Variations of Dynamic Properties in Composites

The use of modal parameter analysis for damage detection in composites is conducted. The finite element method for multilayer plates with different delaminations is used to investigate the relationship between damage location and change of modal parameter. Natural frequencies and mode shapes are computed and their variations induced by delaminations at different positions are analyzed. The numerical result is in better agreement with experiment result than that of reference. The mechanism of the mode-dependent energy dissipation of composite plates due to delamination is revealed for the first time. The result allows of the establishment of guideline for location identification of damage.