EFFECT OF MICRO CHARACTERISTICS OF SOIL-ROCK MIXTURE SLOPE ON FORMATION OF SLIDING SURFACE

As the mechanical properties of soil-rock mixture are complicated, the sliding surface of soil-rock mixture slope is affected by its microstructure characteristics. We established a typical soil-rock mixture slope model with particle discrete element method. The servo mechanism was applied to construct a numerical model with homogeneous stress. Then we calibrated the microparameters of contact model based on the laboratory test data. Combining the strength reduction method, we analysed the difference of the sliding surface morphology between the soil slope and soil-rock mixture slope. The results show that the existence of the block stone causes the nonuniform distribution of the contact force chain, and the block stone increases the slope stability. The development of the sliding surface tends to pass through the gaps between the blocks and is related to the location of block stone. Slope stability is closely related to rock content. As the content of rock reaches 30% ~50%, the landslide is dominated by the movement of local block and cannot form a continuous sliding surface. The study provides the reference for the analysis of failure mechanism of soil-rock mixture slope.