Effects of rock content and spatial distribution on the stability of soil rock mixture embankments

Abstract

Soil-rock mixture embankments are essential for infrastructure stability, particularly in high-fill construction projects. This study evaluates the effects of rock content and spatial distribution of rock blocks on the bearing capacity, stability, and failure sliding surfaces of SRM embankments through static load model tests. An Equation for Sliding Surface of Block-Rock Content and Distribution was developed to calculate sliding surfaces based on rock content and distribution, and validated it through numerical simulation experiments. The results demonstrate that rock content significantly influences embankment stability. When rock content is below 60%, the shear outlet position of the sliding surface increases, and its curvature decreases as rock content rises, thereby enhancing the bearing capacity. Beyond 60% rock content, the internal structure densifies, markedly improving stability, although further increases yield diminishing returns. Additionally, the spatial distribution of rock blocks is crucial; concentrating rock blocks at the slope crest or toe enhances stability, while distributing them in the middle reduces it. These findings offer practical guidance for optimizing the design and construction of the soil-rock mixture embankments, emphasizing the importance of appropriate rock content and spatial distribution to achieve enhanced stability and safety.