Scattering Of SH-Wave By Semi-Cylindrical Alluvial Valley Above Subsurface Structure

In this paper the four kinds of problems with incident SH waves are studied based on the methods of Conjunction, assistant function and multi-polar coordinates: Firstly, the ground motion of a semi-cylindrical alluvial valley above a subsurface circular structure is studied ; Secondly, we researched the ground motion of a semi-cylindrical alluvial valley above multiple subsurface circular structures; The third one is dynamic response of shallow-embedded cylindrical lining cavity below semi-cylindrical alluvial valleys; and dynamic response of multiple shallow-embedded cylindrical lining cavities below semi-cylindrical alluvial valleys is studied at last.Dealing with these problems, the mathematic models are established. The model of a certain problem is divided into three parts: domain I is the semi-cylindrical alluvial valleys; domain II is a half space with a semi-cylindrical canyon; domain III is the subsurface structures. Then the wave functions satisfying zero-stress condition on the horizontal surface are constructed in domain I and II. By using moving coordinate method in complex plan .The condition of displacement continuity stress equilibrium are used to establish algebraic equations at the interface of the two boundaries .Finally, numerical examples are constructed according to the influences of incident angles, wave numbers, material parameters such as: surface ground motion and DSCF(Dynamic Stress Concentration Factor) around the subsurface cavity. The relative conclusions are as follows:(1) Influence of subsurface structures on the surface ground motion is apparent, especially when the structures are "softer" than the half space. In this...