Strip element method to analyze wave scattering by cracks in anisotropic laminated plates

The strip element method (SEM) has been extended to investigate wave scattering by cracks in anisotropic laminated plates. The cracked plates are divided into domains in which the extended SEM is applied. For each domain a set of SEM equations is obtained which gives a relationship between the traction and displacement vectors on the vertical boundaries. These equations are solved by using the conditions at the junctures of the domains. To obtain the time domain response a Fourier transform technique is used, and an exponential window method is introduced to avoid singularities in the Fourier integration. For composite plates with horizontal and vertical cracks, scattered wave fields in both the time and frequency domains are computed, and discussed in comparison with results for uncracked plates. A technique for determining the length of a crack in a plate is also presented. It is shown that the SEM is an efficient technique for the calculation of elastodynamic fields in cracked anisotropic laminated plates.