Propagation Characteristics of Rayleigh Waves in a Partially Saturated Ground

Abstract

Saturation effects of subsoil on the propagation of Rayleigh waves in a half-space have been studied in this paper. Based on Biot's theory, the secular equations of Rayleigh wave are rigorously derived for pervious and impervious surfaces, which are defined as a function of frequency, Poisson's ratio and the degree of saturation. The results show that a slight decrease in degree of saturation can lead to a substantial effect on the velocity, displacement and energy-flux distribution of Rayleigh waves in the low-frequency case, and the influence depends on the Poisson' ratio and the frequency. The propagation depth of Rayleigh waves is about 1.5 times the Rayleigh wavelength and the propagation characteristics of Rayleigh waves are mainly dominated by the shear wave. It is suggested that one may need to carefully take into account the saturation condition in performing SASW method.