Layered rock slope failure is a vital problem in the geotechnical engineering. Based on the equivalent continuum and the compound material mechanics, the layered rock mass is treated as an anisotropic elastic medium. Then, the failure modes of slopes with layered rocks have been studied by numerical simulation using COMSOL software. Numerical results show that the damage zone of the slope first increases then decreases with the increase of layered structural plane angle θ. When θ = 30°, the slope is most easily to destroy. Moreover, the proposed numerical method is applied in Sijiaying iron mine and the results are in good agreement with the actual failure. The successful application shows that the proposed method is reasonable and feasible for the simulation of failure modes of such layered rock slopes.
Layered rock slope failure is a vital problem in the geotechnical engineering, and the research for layered rock slope failure mode is a major issue of realistic significance (Xian 1989). Many methods are used to understand the failure of slopes, each one having its own merits as well as limitations.
The stability of large rock slopes, which are susceptible to rock mass failures, can be analyzed by traditional limit equilibrium methods (Bishop 1955, Janbu 1954) based on assumptions regarding the inclination and location of the interstice forces. For many cases, the limit equilibrium methods have proven to give convincing results despite its limitations. However, to identify failure modes of slopes using the traditional limit equilibrium methods, a range of specified slip surfaces need to be given to simulate the safety factor and the minimum will be recognized as the final slip surface (Baker 1980). This method is not convenient and accurate for rock slope engineering due to the heavy work and randomness in choosing slip surfaces.
The conventional numerical modeling has been developed and has become increasingly popular for complex slope stability analysis. Application of numerical simulation is increasing due to many advantages over limit equilibrium method. A number of landslide studies have been carried out using numerical simulation (Singh et al. 2008, Kripamoy et al. 2012). However, these studies have been done always based on that rock mass per se is still simply treated as isotropic material.