Scattering Of SH-Waves And P-waves By A Circular Alluvial Valley In Wedge-shaped Medium

Site response problem is one of the most important subjects inearthquake engineering. A lot of investigations of earthquake damage showthat the existence of local sites affects the scattering and diffraction ofseismic wave greatly. Hence, there is sensitive variation of earthquakeresponse of ground surface, underground structure and buildings in narrowspatial dimension. Therefore, the investigation of this kind of problem hasimportant meaning on both theory research and practical project.Wedge site is a sort of common topography in practical project. Westudy plane SH-Waves and plane P-Waves in this thesis. Fourier-Besselseries expansion is used to solve the problem. Two very big circles are usedto simulate the free boundary and Graf's addition theorem is used to convertthe coordinates. Finally, the unknowns are resolved on the basis of theboundary conditions and the surface displacement is obtained.The effect of parameters such as the wedge angle, the incident wavefrequency and the angle of incidence is also analyzed. Furthermore, theaccuracies of the numerical results are checked by the convergence of theground surface displacement and residual errors of boundary conditionswith the increasing progression term. The results demonstrate that theamplification of incident wave almost occurs around the vertex of thewedge due to plane SH-Waves or P-Waves. The degree of amplification isvariable with the wedge angle and incident angle.