Study On The Two-dimensional Scattering Of Plane-P-waves And Plane-SV-waves By Underground Cylindrical Lined Cavity In A Fluid-saturated Porous Media Half Space.

Irregular surface topography and geological conditions may have significant effect on the amplification of seismic ground motion and generate concentrated damage to building and other civil engineering structures. Many seismic records and theoretical analysis indicate that the earthquake motion of the site where the earthquake disaster is more severe is large than the flat or regular site. Which indicate that the effect of the complex local site on the earthquake motion cannot be ignored. In this thesis, the earthquake ground motions of local irregular sites with saturated soil was investigated by analysis and numerical simulation, and a series of results were obtained.Firstly, on the basis of Biot dynamic theory, a series of analytical solutions for scattering of plane waves by lined cavity local irregular site were developed using Fourier-Bessel series expansion technique:(1) analytical solutions for the scattering of plane P waves by underground cylindrical lined cavity in a fluid-saturated porous media half space.(2) analytical solutions for the scattering of plane SV waves by underground cylindrical lined cavity in a fluid-saturated porous media half space.Secondly, on the base of the analytical solutions mentioned above, the numerical results were given to illustrate that the dynamic stress concentration factor on the wall of the lined cavity not only depend on the lined cavity diameter, but also depend on the dimensionless frequency of the incident waves (incident frequency, incident angel) , the material parameters, and the boundary conditions.The above study results will have reference value on the earthquake reflect analysis and designing of the underground cylindrical lined cavity complex site.