A mechanical model of a granulated media impregnated with liquid is constructed. The problem of determining dynamic characteristics (density, dissipation, elasticity, etc.) is formulated. On the basis of an adequate mathematical model, we analytically calculated the eigenfrequencies of the principal and higher modes of the hydroelastic system and found their shifts with respect to the frequencies of the unperturbed system (without the presence of the medium). The resonance curves and values of shifts determined in precision experimental measurements make it possible to find the dynamic density, the dissipation coefficient, and the speed of sound (the elasticity) in the medium with a relatively small error. As the hydroacoustic installations, we used the resonators on the basis of acoustically rigid metal tubes and rectangular vessels with acoustically soft walls and with a soft or rigid bottom. The vessels are filled with liquid (water, kerosene, oil, etc.) with an open surface and contain samples of the granulated media under investigation.
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