Study on reflection and transmission characteristics of shear waves at sediment layer interface

Since most of the natural disasters in the Yellow River are caused by sediment, the study of sediment composition, erosion and transport law is a fundamental part of sediment management in the Yellow River. As a method of in-situ testing, shear wave detection can obtain physical parameters such as the shear modulus of sediment. This paper, based on the Biot—Stoll model, deduces the equations for calculating the reflection and transmission coefficients when a shear wave is incident at the interface between sediment layer, and analyzes the effects of frequency, incident angle and porosity on the reflection and transmission coefficients of shear waves, as well as the differences in the propagation characteristics of longitudinal and shear waves at the interface between sediment layer. The results indicate that the reflection and transmission coefficients of shear waves are linearly related to the porosity of sediment, and the reflection coefficient of shear waves increases with the increase of porosity. The incident angle has a great influence on the changes of the reflection and transmission coefficients of shear waves, especially near the critical angle, the coefficients change abruptly. The frequency has a great influence on the reflection and transmission coefficients of shear waves only near the characteristic frequency of sediment, while deviation from the characteristic frequency, the influence is small. The research results have certain significance for obtaining the physical parameters of sediment and analyzying the composition of the Yellow River sediment and its erosion law.