Rayleigh waves in an orthotropic half-space coated by a thin orthotropic layer with sliding contact

In the present paper, we are interested in the propagation of Rayleigh waves in an orthotropic elastic half-space coated with a thin orthotropic elastic layer. The contact between the layer and the half space is assumed to be smooth. The main aim of the paper is to establish an approximate secular equation of the wave. By using the effective boundary condition method, an approximate secular equations of third-order in terms of the dimensionless thickness of the layer is derived. It is shown that this approximate secular equation has high accuracy. From the secular equation obtained, an approximate formula of third-order for the Rayleigh wave velocity is derived and it is a good approximation.