Evaluation and analysis of the causes of a landslide and treatment measures during the excavation of a tunnel through a soil-rock interface

Abstract

Combined with the results of field tests and field investigations, the upper-bound finite element adaptive encryption method based on the strength reduction method was used to study the causes of a landslide during the construction of a mountain tunnel passing through the interface between upper soft and lower hard strata, and the effects of different treatment measures were evaluated. The results show that the continuous occurrence of rainfall, the presence of loose soil, bedding planes and biased topography were the main causes of the landslides. Anti-slide piles + backfilling + slope brushing protective measures effectively improved the stability of the slope, but the stability of the rock surrounding the tunnel must still be considered. Through subsequent observations inside and outside the tunnel, it is evident that the deformation of the mountain and surrounding rock around the tunnel were effectively controlled after adopting the above treatment measures. These research results can provide theoretical and technical references for the analysis, prevention and treatment of landslides in similar projects.