Scattering of Rayleigh-waves by surface-breaking cracks:: an integral formulation

Several crack configurations are considered in order to show the importance of the cracks' geometry on the Rayleigh-wave propagation. We use the Indirect Boundary Element Method, this numerical technique is based on an integral representation of the diffracted wave field, which has been reduced from Somigliana's identity. The method allows us to evaluate the complete displacement field by the superposition of the free field and the diffracted field. It is remarkable that the free field is specified as incident Rayleigh-waves, making the assumption of absence of cracks. The diffracted field is obtained from the integral representation by means of the presence of cracks. Our results are compared with those previously published. We emphasize the amplitude reduction of Rayleigh-waves while the interaction with the cracks take place. Conspicuous wave amplification at the crack neighborhood is observed immediately after such interaction. This information may give us a way to characterize crack's depth and orientations from the analysis of the diffracted field.