Numerical Study of the Influence of the Spatial Distribution of Oversized Rock Blocks on the Stability of Soil-Rock Mixture Slopes

Soil-rock mixtures (S-RMs), as special engineering geological materials, are widely distributed in mountainous regions and are important hosts of slope disasters. Stability studies are very important for predicting S-RM slope safety during the construction and operation of engineering projects. To investigate S-RM slope stability considering the spatial distribution of oversized rock blocks in the slope, the distinct element method (DEM) program particle flow code in two dimensions (PFC2D) was used to analyse the stability of slopes composed of S-RMs. First, according to the stochastic approach, different numerical models of an S-RM slope were established with different oversized rock block spatial distributions. Then, the S-RM slope models were simulated, the safety factor and sliding characteristics of the slopes were analysed, and the unbalanced contact force and rotational characteristics of the oversized rock blocks were discussed. Finally, the concept of key rock blocks in S-RM slopes was proposed, and their spatial distribution characteristics and influence characteristics were summarized. The findings of this study suggest that oversized rock blocks have a certain influence on the stability of S-RM slopes.