Stability of stepped sliding of bedding rock slopes with discontinuous joints

The bedding rock landslides with stepped sliding surface are common in engineering, and the characteristics of rock bridges and joints are very important to the formation of stepped sliding surface. The weakening characteristics of the strength parameters of rock bridges and joints are considered. The models for stability of stepped sliding of bedding slopes are established. The results show that the accuracy of the model is verified by comparing with the planar failure model. In addition, the fracture connectivity rate k_Y, basic friction angle φ_b, roughness coefficient JRC and weakening coefficient K_c have significant influences on F_s. In this mode, the greater β₃ is, the more significant the reduction of F_s is, and the more unstable the slope is. In addition, the excavation times and slope angle have significant influences on the slope stability. The difference rate between the proposed method and the limit equilibrium solution is less than 1%. In some cases, when the joint surfaces are exposed by excavation, F_s is significantly reduced (the reduction of 22.8% when β=53°), which easily leads to the occurrence of landslides. Meanwhile, with an increase in angle β₁ of tensile cracks and height h_w of water, F_s significantly decreases. The water pressure is more significant when the outlets are blocked, and the rock slope is most unstable.