Elastodynamic Doppler effects and wave energy partition by a sliding interface

Abstract

Wave reflection and refraction at a sliding interface are discussed. The regular dynamic friction rule, Coulomb’s law, is assumed for the sliding interface. Doppler frequency shift is found, and it depends on the ratio of a sliding velocity to an apparent horizontal velocity of an incident wave. Wave energy partition by the sliding interface is also discussed. In the case of an incident P-wave, a transmitted/refracted P-wave gets the major part of the incident wave energy. On the other hand, in the case of an incident SV-wave, a reflected SV-wave gets most of incident wave energy. It is also found an energy supply or loss by the sliding interface. It strongly depends on the friction coefficient and on the sliding direction. Further, it is shown that there is no possibility for detecting the sliding velocity by means of Doppler frequency shift.