Abstract: The deformation of reservoir landslides exhibits a significant coupling effect between seepage and creep. In this study, we investigated the influence of seepage on creep and the impact of deformation on seepage using a self-developed seepage and creep coupling triaxial apparatus. By redesigning and improving the GDS triaxial apparatus, we conducted seepage and creep coupling tests with precise control and measurement. Our findings reveal that under the influence of seepage, the volume deformation of soil samples gradually increases with time and then slowly decreases. This behavior is attributed to excess pore water pressure leading to the unloading of confining pressure, resulting in rebound deformation of the soil sample. Despite this, the ongoing effects of seepage pressure continue to act on the soil, contributing to a gradual decrease in sample volume. Furthermore, we obtained the data of volume changes of soil samples during the seepage process and established the void ratio-permeability coefficient (e-k) relationship curve before seepage and after achieving seepage stability. The results demonstrate that considering the influence of deformation yields a more accurate e-k relationship curve, better reflecting the fluid-solid coupling effect of the soil. These research findings are expected to contribute to the development of a more scientific and rigorous theory and method for predicting the evolution of deformation in reservoir landslides.

Key words: reservoir landslide, creep, seepage, fluid-solid coupling, volumetric strain