Exploring failure evolution of anti-dip slate slope using centrifuge test and discrete element method

Toppling failure commonly occurs in anti-dip slate slopes due to foliation splitting and gravitational deformation. The study uses centrifuge tests and the discrete element method (DEM) to investigate the influence of foliation and existing fractures on the toppling failure evolution of anti-dip slopes. Six centrifuge tests with slate blocks obtained from an actual slope were carried out. Then, a proposed foliation model was implemented in the DEM software 3DEC to simulate the failure evolution of anti-dip slopes. The 3DEC analysis was validated by the actual failure pattern of slopes in centrifuge tests. The results indicate that the toppling failure of the anti-dip slope was initiated by existing fractures rather than the original cohesive foliation. Though the slate foliation is regarded as a weak plane in the rock mass, it retains a higher strength than the existing fracture, so the toppling failure is difficult to initiate from the cohesive foliation. The closer the fracture is to the free surface, the more pronounced the damage. In addition, the simulation indicates that the existing fracture's position also affects the anti-dip slope's failure degree. The fractures on the top propagate more easily than those on the bottom.