Propagation of SH waves in a layered half-space with a frictional contact interface

The propagation of SH waves in a layered half-space with a frictional contact interface is considered. The incident wave is assumed to be sufficiently strong so that friction may be broken, and the local slip may take place at the interface. In the stick zones, both the displacements and stresses are continuous, while in the slip zones, the Coulomb friction model is adopted. The mixed boundary conditions lead to recurrence relations for the subcritical angle incidence or singular integral equations for the supercritical angle incidence. The extent and location of slip zones, which are unknown before the solution of the problem, are determined. The local slip velocities and the interface shearing tractions are calculated in detail for the subcritical angle incidence. The results show that the solution of the problem is dependent on the frequency of the incident wave due to the presence of the characteristic length—the thickness of the elastic layer. It is also found that, in some situations, there exist four slip zones instead of two over one representative period. All these features are quite different from those for infinite media.