Elastic SH wave propagation in a layered anisotropic plate with interface damage modelled by spring boundary conditions

Elastic SH wave propagation in a layered anisotropic plate with interface damage is modelled in several steps. A single interface crack between two half-spaces is first studied and an explicit solution for the crack-opening displacement is obtained at low frequencies. This is then generalised to a random distribution of cracks at the interface and the result is reformulated as a spring boundary condition. As an example of its usefulness, this boundary condition is then used in the derivation of a plate equation by expanding the displacements in power series in the thickness coordinate.