Complex sliding characteristics of landslides and evaluation of the reinforcement with arched anti-slide piles based on 3D discrete element method: a case study

Landslide movement processes often exhibit complex paths, introducing the uncertainty of landslide movement paths, and challenging landslide hazard prediction and pre-disaster prevention and control. In this study, we employed numerical simulations to investigate the dynamic processes with complex paths of the Pangjiawan landslide using the 3D discrete element method. A scenario simulation was conducted to evaluate the stability of the landslide, incorporating arched anti-slide piles, and the reinforcing effect of arch anti-slide piles on the Pangjiayan landslide under different rise-span ratios and pile spacing was analyzed in depth. The results indicate that the Pangjiawan landslide in mountainous notch topography exhibits a complex movement path with turning and convergence behaviors, and arched anti-slide piles are more effective in stabilizing the landslide than traditional linear anti-slide piles. When the embedded depth of the arched anti-slide piles remains consistent, higher rise-span ratios result in more significant synergistic effects between the piles and the surrounding soil. Moreover, even with increased pile spacing and a reduction in the number of anti-slide piles, the landslide displacement after reinforcement with arched anti-slide piles is lower than traditional linear anti-slide piles. The research provides valuable insights into the dynamics of landslide movements, emphasizing the superior reinforcement capabilities of arched anti-slide piles. This contributes to our understanding of landslide mitigation strategies in challenging topography.