The structural characteristics of soil-rock mixture (SRM) slopes, including the content, shape, size, and spatial distribution of rock blocks, can significantly influence their failure mechanisms and factor of safety (FOS). Defining the structural characteristics of SRM slopes for stability analysis remains challenging. This study proposes a method for establishing random models and evaluating the statistical properties of the FOS values of SRM slopes. Accordingly, the SRM slope models were constructed by considering the random properties of the shape, size, and spatial distribution of rock blocks in the slope domain. A slope failure criterion based on energy changes and the combined subroutines of USDFLD and URDFIL was implemented in the ABAQUS finite element software to determine the FOS values of the SRM slopes. Monte Carlo simulations were performed to assess the statistical properties of the FOS for random SRM slopes varying rock block properties. The results indicated that when the rock block content was greater than 30%, the stability of SRM slopes considerably increased. For a rock block content of 40%, the effect of rock block size on the SRM slope stability followed two different trends: the mean FOS value tended to decline and subsequently increased as rock block size increased. However, this trend was not observed on SRM slopes with a 30% rock block content. Besides, the dispersion of the FOS values gradually increased with increasing rock content and rock block size. Furthermore, the soil-rock interface strength affected the stability and failure mechanism of SRM slopes. These findings enhance comprehension of the SRM slope stability assessment and demonstrate improved accuracy in predicting and mitigating damage.

The rock-soil mass, subjected to complex and lengthy geological processes, exhibits heterogeneity which induces variations in mechanical properties, thereby affecting the overall stability of slopes. In this paper, a novel numerical model that incorporates the Weibull distribution function into the meshless numerical manifold method based on the strength reduction method (MNMM-SRM) to account for the slope soils heterogeneity and their influence on the factor of safety (Fs) and the critical sliding surface (CSS). Initially, the Weibull distribution is introduced into the MNMM-SRM model based on the complementary theory of subspace tracking, addressing the issue of multiple yield surface corners in the Mohr-Coulomb framework while simultaneously considering the heterogeneous nature of rock and soil formations. Subsequently, an intelligent method based on unsupervised learning is proposed to obtain reasonable CSS, utilizing the total displacement field at slope nodes and the equivalent plastic strain field as input variables. The results serve as criteria for terminating the strength reduction in the MNMM-SRM. The applicability of this method is verified through three typical examples, demonstrating its potential for widespread application in the assessment of heterogeneous slope stability.

Numerous manually excavated loess caves are present within a cultural relic protection zone in the northwestern region of China. The collapse of these caves frequently leads to the cracking, tilting, and even collapse of ancient buildings above, posing a severe threat to the safety of cultural architectural relics. Investigating the stability and characteristics of deformation and failure in loess caves is essential for effectively reinforcing and protecting cultural relics. A twodimensional model of a loess underground cavern was developed using OptumG2. The stability and modes of deformation and failure in the underground cavern were analyzed through the augmentation of soil gravity and the strength reduction method. This analysis determined the cavern's safety factor, force, deformation and damage mode, and the plastic zone's progression. Numerical simulations analyzed the force characteristics of the support structure under different stress release ratios. The findings revealed that, with the implementation of an anchor rod concrete lining support scheme, the most probable failure mode is a shear failure, initiating at the arch foot. The ground's stress release rate does not influence the safety factor of the cavern but rather the material, design, and strength of the support structure. However, the magnitude of the internal forces acting on the supporting structure by the soil in the cavern is related to the degree of ground stress release. When applied during significant stress release, support structures may experience reduced internal forces, albeit with more substantial stratum displacement; opting for an appropriate stress release when applying support structures is crucial for achieving optimal stratum displacement and lining internal forces.

There are many factors affecting the stability of open-pit mine slopes, among which slopes with soft interlayers have become an important factor inducing deformation and instability due to their poor mechanical properties. In this paper, for the destabilization of a slope with soft interlayer under rainfall infiltration in an open-pit mine in Zhejiang Province of China during the rainy season, a sudden change of displacement at the monitoring point and the formation of a continuous plastic deformation of the slope are proposed as the criteria for slope destabilization through the establishment of a rainwater seepage-stress coupling model combined with the strength reduction method, and by using COMSOL Multiphysics finite element numerical simulation software to establish a three-dimensional numerical model based on the actual mining slope conditions. The safety principle is introduced through the strength reduction method to analyze the stability of the slope with soft interlayer under the coupling effect of seepage and stress. The safety coefficients of the slope with soft interlayer are calculated by using Numerical methods under the coupling effect of seepage and stress. The influence of rainfall intensity and duration on the stability or safety factor of the slope with soft interlayers was studied through analysis of stress, saturation, displacement, and pore pressure evolution. The mechanism of rainfall affecting slope stability was investigated, and the findings were validated using an engineering case study of a slope with a soft interlayer. The findings show that rainfall intensity is the main factor affecting slope stability in the open-pit mine slope with soft interlayer. The higher the rainfall intensity, the faster the shallow soil forms a saturation zone, whereas soft interlayers speed up the process and endanger slope stability. The slope prevention and control technology of the prestressed anchor cable (rod) framework was proposed based on the slope management construction conditions of the mine, and the effectiveness of the measure was verified through on-site industrial tests. The research findings provide a reference for preventing and controlling slope with soft interlayers in open-pit mines under similar conditions.