Three-Dimensional Numerical Investigation on the Seepage Field and Stability of Soil Slope Subjected to Snowmelt Infiltration

Cutting slope failures occur frequently along the high-speed railways in Northeast China during the construction due to snowmelt infiltration. This study addresses this issue by applying a three-dimensional numerical model. The influence of the depth of accumulated snow (ds), daily temperature variation (ΔT), and freeze-thaw (F-T) cycles on the seepage field and stability of cutting slopes is discussed. The results demonstrate that water seepage due to snowmelt infiltration primarily extends through the ground surface by about 10 m. The deep-seated instability is likely to occur under a prolonged and highly accumulated infiltration, while shallow failure is associated with intense, short-duration snowmelt infiltration. The maximum degree of saturation (Sr) and pore-water pressure (PWP) values are observed at the slope toe. Increasing ds and ΔT increase the Sr and PWP due to snowmelt infiltration and thereby decreases cutting slope stability. Compared to the ds and ΔT, the F-T cycle is more likely to cause slope failure. In addition, the F-T cycle also induces the reduction of soil strength and the crack propagation. Overall, the conducted study provided useful help toward the process of safer design for cutting slope along the high-speed railway in seasonally cold regions.