AN INDIRECT BOUNDARY-ELEMENT METHOD BASED ON RECURSIVE MATRIX OPERATION TO COMPUTE WAVES IN IRREGULARLY STRATIFIED MEDIA WITH INFINITELY EXTENDED INTERFACES

An Indirect Boundary Element Method that uses the full-space Green's f unction is proposed for the calculation of in-plane seismic response o f irregularly stratified media with buried interfaces extended infinit ely. The method uses the solution for horizontally stratified media ob tained by the Thomson-Haskel propagator matrix method in the wavenumbe r domain as the reference solution. A recursive matrix operation is in troduced to solve the boundary integral equations, which in turn facil itates the calculation of multi-layer problems, preventing excessive r equirements of computer main memory. The proposed formulation efficien tly eliminates non-physical waves due to numerical truncation.