基于离散元的边坡弯曲倾倒渐进破坏特征分析

发生弯曲倾倒的边坡一般存在一组优势的陡倾不连续面，岩层在自重或外力作用下向临空面弯曲变形，表现出明显的柔性特征。基于物理模型试验建立了相应的离散元计算模型，模拟了边坡弯曲倾倒的渐进失稳过程，系统剖析了岩体弯曲倾倒的力学机制和破坏特征。结果显示，塑性区贯通是边坡弯曲倾倒失稳的必要非充分条件，悬臂岩柱在弯折过程中其内部应力表现出明显的不均匀性。进一步探讨了关键力学参数对倾倒破坏面的影响规律，具体表现为破坏面倾角随节理摩擦角的增大而增大，而节理黏聚力和岩体抗拉强度对其影响并不显著。研究成果可为倾倒边坡的分析设计提供科学参考。

Analysis on Progressive Failure Characteristics of Slope Flexural Toppling Based on Discrete Element Method

A set of dominant steeply inclined discontinuities generally exists in flexural toppling slopes. The rock mass bends and deforms to the free surface under self-weight or external forces, showing obvious flexible features. Based on a physical model test, a corresponding discrete element model was established to simulate the progressive failure of slope flexural toppling. Meanwhile, the mechanical mechanism and failure characteristics of rock flexural toppling were systematically analyzed. The results show that the plastic zone penetration is a necessary and non-sufficient condition for the failure of such slopes, and the internal stress of the cantilevered rock shows inhomogeneity in the bending process. Further, the influence law of key mechanical parameters on the fracture surface was explored. It is concluded that the dip angle of the fracture surface increases with the increase of joint friction angles, while the influence of joint cohesion and rock tensile strength is not significant. The research can provide scientific reference for the analysis and design of toppling slopes.