中国西部深切峡谷区某崩滑体成因机制与稳定性分析OACHSSCD

The geological environment in a deep canyon area of western China is complex,with intense tectonic activities and numerous geological disasters such as landslides and collapses.The causes are diverse,and the stability of the accumulation bodies has drawn much attention.This paper analyzes the environmental conditions for the formation of large accumulation bodies and their deformation and failure modes through field geological investigations and geotechnical tests,and uses FLAC3D to simulate the stability of accumulation bodies under heavy rainfall.The research results show that the accumulation body is composed of multiple high-altitude landslide and collapse accumulation bodies,with a volume of approximately 2.9×106 m3,and is a large-scale landslide and collapse body.Its front edge overhangs the fifth-level terrace,and the sliding bed is composed of mixed schist and gneissic granodiorite.The sliding source area is located on both sides of the upper and lower plates of the strike-slip fault.The formation process consists of three stages:unloading rebound,shear sliding along the large structural plane on the inclined slope,and multiple instabilities triggered by high-intensity events.The deformation and failure mode is classified as"sliding-tensile cracking type".The accumulation body is currently stable,but under the influence of heavy rainfall,local instability may occur.