Study on deformation and failure mechanism of low-dip red bed slope with soft-hard interbedded structure: a case study of Chishui, China

Taking the Chishui Wanglong slope as a case study, the actual deformation characteristics of the slope were obtained through geological field surveys. Using the base contact friction experiment and PFC discrete element numerical simulation, the deformation and failure mechanism of the low-dip red bed soft-hard interbedded slope were investigated. The results indicate that the Wanglong slope is a typical low-dip red bed slope with a soft-hard interbedded structure, characterized by falling and toppling failure as the primary deformation modes. The deformation and failure of the slope are primarily controlled by the depth of the concave cavity formed by differential weathering. Comprehensive analysis reveals that the slope's deformation and failure evolution process can be described as unloading cracks expansion stage, differential weathering stage, and slope deformation and failure stage. The findings of this study can be applied to develop a theoretical framework for determining the prevention and control measures of this type of engineering slope in the Chishui red bed area, which is crucial for reducing the potential risk of geological disasters.