A SIMPLE, COMPLETE NUMERICAL-SOLUTION TO THE PROBLEM OF DIFFRACTION OF SH-WAVES BY AN IRREGULAR SURFACE

A new method is presented to calculate the diffraction of elastic SH waves by irregular surfaces. The technique developed is applicable to boundaries of arbitrary shape and steepness as well as to periodically corrugated surfaces; it is valid at all frequencies. The approach consists of determining the surface forces which cancel the incident stress along the surface. The method relies on the introduction of a periodicity in the surface shape and on a discretization of the boundary at regular spacing. The surface sources which radiate the scattered wave field are obtained by iteration. Examples of calculations and comparisons with other methods are presented.