Scattering Of Plane P Waves By A Tunnel In Saturated Half-Space

In actual projects, scattering and diffraction of earthquake waves by the large,underground tunnel structures can affect the ground motion near the tunnels, it caneven affect the buildings on the ground nearby. Therefore, to solve this kind ofproblem has important meaning on both theory and engineering application.The unknowns in scattering waves subjected to incident plane P wave areresolved based on the boundary conditions in the form of Fourier-Bessel series, thesurface displacement is calculated according to these. Furthermore, the effect offactors such as incident angle, incident frequency on the surface displacement is alsoanalyzed. The boundary conditions are also validated.Some conclusions are given at the end of the thesis: the underground circulartunnels can greatly amplify the surface displacement which is induced by the incidentplane P wave in the saturated half-space. When the frequency is the same, thesurface displacement is increasing with the porosity accordingly. The surfacedisplacement is greater in the undrained interface than that in the drained interface.