Study on the reflection and transmission of P wave on the interface between elastic medium and saturated frozen soil medium

Based on the theory of elastic wave propagation in frozen saturated porous media and single-phase elastic media, the reflection and transmission of plane P wave on the interface between saturated frozen soil media and single-phase elastic media are studied. According to the Helmholtz vector decomposition theorem and the boundary conditions of the interface, theoretical expressions of transmission amplitude ratio and reflection amplitude ratio of plane P wave from single-phase elastic media to saturated frozen soil media are derived. Through numerical calculation, the relationships between the transmission amplitude ratio/ reflection amplitude ratio of elastic wave and incident angle are analyzed under different incident frequencies, cementation parameters, porosities, saturations and contact parameters. The results show that only the reflected P wave and three types of transmitted P waves are generated when the P wave is incident vertically from a single-phase elastic medium to the interface of the saturated frozen soil medium. When the grazing incidence occurs, only reflection occurs without transmission. The incident frequency, cementation parameters, porosity, saturation and contact parameters have significant influence on the amplitude ratios of reflected wave and transmitted wave.