Structural Damage Detection by Using Finite Element Method as Function of Length

Abstract

The work concerned exactly a structural damage. In this paper also involves the effect of length on the damping of the composite. The calculation of laminate damping is performed by use of a strain energy method. The modal analysis of the structure for different loading rates is based on the analytical method used to solve the equation of free vibrations. The difference between strain energies for both cases (damaged and undamaged) are calculated by the finite element method. The structural damping of the different beams is evaluated from these energies. The results deduced from the damping by finite element analysis for the first three modes that the evaluation of laminate damping takes account the variation of the structural damping η with lengths. This study shows clearly the decrease of one of dynamic characteristics especially the frequency when the loading rate increases for all lengths studied; this should have high utility as a decisive test for non-destructive damage detection.