Elastic Wave Scattering By Fault Site

Faults are widely existed in crust. They effect the elastic wave scattering as site condition. The analysis of wave propagation by fault is important both in theory and engineering. Results of wave scattering by both fault with fracture and fault without fracture are present in frequency domain first time using IBEM,to which the dynamic stiffness matrix and Green function for distributed loads acting on inclined line founded by Wolf are applied.Displacements of site with fracture zone by SH, P, SV waves are calculated. Analysis about how the factors effect the ground motion has been done, which reveals an important law about wave scattering by narrow fault. It is improved that even if fracture zone is very narrow, great amplifying action maybe happen.SH, P, SV waves scattering by fault in layered site have been studied. There is remarkable difference between the response of layered site and homogeneous site with fracture. Layer-Fracture interaction can bring large displacements near fracture in layer site.In addition, SH wave scattering by finite fault without fracture is analysed using IBEM. The Factors, such as drop height, stiffness ratio of two sides, dip angle, have great effect on wave scattering. As for the fault with drop,when drop height is equal to wavelength,there is bigger displacements than other drop height. As for the fault without drop,if stiffness of two sides is different, displacements on soft part maybe large generally. It's especially obvious when waves come from soft part.