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A laser vibrometer is used to measure waves generated by a piezoelectric transducer in a solid steel sphere. The spatial and temporal resolution make it possible to verify the theoretical dispersion relation of spherical surface waves. In particular, the a ...
Low-frequency waves generated by an impact on an isostatic granular medium with vanishing confinement pressure are theorized to depend on rigid-particle collisions. According to this model, an impact generates a solitary wave spanning several particle diam ...
Wave propagation in cellular and porous media is widely studied due to its abundance in nature and industrial applications. Biot's theory for open-cell media predicts the existence of two simultaneous pressure waves, distinguished by its velocity. A fast w ...
Wave propagation in granular solids is found to have at least two regimes: a low-frequency ballistic signal and a high-frequency diffusive tail. The latter is attributed to granules clapping or elastic waves within the granules themselves. The low frequenc ...
The physical mechanism of elastic wave propagation through granular solids is investigated. Based on the symmetry of a one dimensional chain of spheres, spherical surface waves are considered to be responsible for the energy transport. A simple mathematica ...