Analytical Solutions For Scattering Of Rayleigh Waves By Alluvial Valleys With Saturated Soil Deposits

Scattering and diffraction of earthquake waves by alluvial fields can affect the ground motion and architectures nearby on the ground. Therefore, it is important to solve the problem in theory and in engineering application.Analytical solutions for the scattering of alluvial valleys subjected to the incident plane Rayleigh waves were derived in the thesis by the Fourier-Bessel series expansion technique. The conditions in regard to the alluvial valleys with saturated soil deposits. The accuracy and convergency of the solution are tested, too. The method of wave function expansion was adopted. The potential functions in free field were derivated firstly, then they were expanded on the corresponding boundary by the Fourier-Bessel series expansion technique.Results show that such factors affect the ground motion to different extent as the interface condition, the ratio of thickness and width, the porosity and so on. It was shown that the alluvial layer amplifies incident plane Rayleigh waves tremendously, and the amplification can be more than two times than that for a simple field without the alluvial layer; the ratio of thickness and width and the porosity also have great effects on the field dynamical characteristic.