FREQUENCY DISPERSION OF ELASTIC-WAVES IN DISORDERED COMPOSITES

A version of the non-local theory of disordered composites (of randomly disordered media in a broad sense), which is constructed in terms of effective characteristics, is proposed. The latter are functions of a wave vector and frequency which enables one to describe the effects of spatial and frequency dispersion in wave propagation. The propagation of elastic waves solely taking account of frequency dispersion is investigated since little attention has been paid to this question. Results are obtained in the strong dispersion approximation, which corresponds to the long-wave but high-frequency approximation.