Abstract:In order to accurately analyze the stability of soil-rock slopes, based on the original rock shape library, a random soil-rock slope model establishing method was proposed. This method could consider the shape and distribution characteristics of rocks very well. Using this method, finite element limit analysis software Optum G2, combined with physical models, the stability of soil-rock slope considering different rock contents (0～50%), long axis inclinations (0°～180°) and soil-rock contacting surface (0.01～1.40) were studied. The results showed that the influence of rocks on the shear zone of the slope included three development modes: “bypass”, “diversion” and “include”, which lead to the change of bending point, length and developing direction of the shear zone. Through the study on the stability of slope with different rock contents, it was found that when rock content was more than 20%, the influence of rock distribution on the stability of slope was greater, and the slope with high rock content was prone to “local” or “disintegrating” failure. At the same rock content, the minimum (or maximum) safety factor was obtained when the long axial inclinations of rock blocks were parallel (or vertical) to the shear zone of the slope. When the rock long axis was vertical to the shear zone of the slope, the slope was prone to “disintegration” failure, which was mainly related to the “induced” effect of the rock long axis on the shear zone of the slope. Under the same rock distribution model, the slope safety factor decreased with the decrease of the soil-rock contacting surface coefficient, and when soil-rock contacting surface strength was lower than that of the soil, the “attraction” effect of rocks to development of the shear zone would appeared. The research results could provide a reference for the stability analysis and treatment of soil-rock slopes.