Stability analysis of Middle Pleistocene ice-water sediment landslides in the western Sichuan Depression

Abstract

To study the deformation destruction mechanism and stability of the Middle Pleistocene ice-water sediment landslide in the western Sichuan Depression, this paper takes the K1887+350 landslide in the Chengdu-Yaan section of the G5 Beijing-Kunming Expressway as an example. Engineering geological surveys, physical and mechanical tests, and comprehensive monitoring are applied. Based on the actual deformation of the landslide, the paper analyzes the deformation and destruction mechanism of the landslide and studies the stability of the landslide before and after the reinforcement treatment and comprehensive monitoring technology. The results show that an unfavorable geological structure, slope toe, and precipitation induction are the main reasons for the deformation and instability of the K1887+350 landslide. The swell ability of fine-grained soil in the Middle Pleistocene ice-water sediment layer further reduces the soil shear properties. The long-term infiltration of atmospheric rainfall eventually leads to the superficial creep-pull deformation of ice-water sediments. Surface crack monitoring is an effective way to judge the current state of a mountain and analyze the stability of a landslide