This paper presents a new model of the load sharing law with a three-stage load sharing pattern via a representative case study in the Three Gorges reservoir region, China. A definitive new three-stage load transfer pattern is presented, including end-bearing soil arching, friction soil arching and the sliding mass in front of the pile. By means of the soil arching effect between the anti-sliding pile and landslide mass, the law of the load sharing ratio under different cases, including different intervals, section dimensions, driving forces, and shearing parameters of the sliding mass and the pile-soil interface, is presented by using the explicit finite-difference numerical modelling method. The results show that (a) the effect scale of the soil arching effect is within the scale of four times of the width of the pile; (b) the soil arching only exits within a certain pile interval, and it will become inefficiency beyond the maximum pile interval; (c) there is a threshold value for the cohesion strength parameters of the sliding mass, beyond which the load sharing ratios of soil arching keep in a steady level.

Surface roughness is one of the most important parameters that have significant influence on the mechanical and hydraulic characteristics of rock joints. To investigate the evolution of surface roughness under normal and shear loads, direct shear tests and numerical modeling based on the discrete-element method (DEM) were performed; bright area percentage (BAP), which places emphasis on the contact areas, was used as an index to describe the roughness. The results demonstrate that the surface roughness of rock joints decreased gradually as the shear displacement increased, and then roughness experienced a significant reduction in the residual stage and remained constant. Furthermore, the evolution of surface roughness was found to depend on the normal stress and shearing direction. Reduction in the degree of joint roughness with high normal loads was lighter than that with lower normal loads, and roughness varied with shear directions. The numerical simulation method proposed in this study has the...