Mechanical Characters of Anti-Sliding Piles of Landslide with Double Sliding Zones Based on Finite Difference Method

Existing theoretical analysis of the deformation and internal force of anti-sliding piles are mostly designed for single-sliding zone landslides, while most of the accumulation layer landslides in the Three Gorges reservoir area develop double sliding zones. Considering the difference in material composition of landslides with double sliding zones, a generalized model for the interaction between landslides with double sliding zones and anti-sliding is constructed. to study the internal force and deformation of anti-sliding piles. Then a calculation method of landslide thrust under double-layer sliding condition is proposed to derive the equations of deformation and internal force of anti-slide pile in landslides with double sliding zones based on the foundation coefficient method and the finite difference principle. Numerical simulation method was used to research the distribution laws of landslide thrust and verify the newly proposed approach via the Majiagou landslide as example. The results of the theoretical and numerical simulation methods well show the sliding characteristics of landslides with double sliding zones. Meanwhile, the distribution of the deformation and internal forces show a great regularity: the displacement of the pile decreases gradually from the top to bottom accompanied by reverse bending phenomenon, the shear force and bending moment of the pile exist two maximum values and one minimum value, and the maximum values of the shear force are located at the sliding surface while the maximum values of the bending moment are located 2~3 m below the sliding surface, and the minimum value is located in the deep sliding body. In addition, the distribution of landslide thrust and the vital design parameters of anti-sliding piles are important factors that affect the mechanical characteristics of the pile. The proposed method can provide a theoretical reference for the design of anti-sliding piles of landslide with double sliding zones.