Resumen de Wave scaterring by a periodic array of in-plane cracks at the interface between dissimilar media

N. Favretto-Cristini

• We investigate analytically the behaviour of time-harmonic elastic waves in the neighbourhood of a plane interface between dissimilar elastic media, where a periodic array of in-plane cracks exists. Waves incident on such a boundary excite a lot of propagating and evanescent scattered waves, and the incident energy is subjected to a complicated process of redistribution. The aim of the work is to quantify the amount of incident wave energy partitioned among the propagating scattered waves. The scattered fields are expressed in terms of Fourier series with coefficients depending on Legendre functions. Energies associated with the scattered waves are evaluated as a function of the incidence angle, and results are presented for three different distributions of the cracks at the interface. We show that the amount of the reflected wave energy and the amount of the diffracted wave energy increase with increasing percentage of cracks at the interface. We also suggest that, contrary to the case of an interface between identical media, the energy conservation law cannot be applied in the work presented here since phenomena associated with interface wave scattering are not taken into account.