The deformation and failure characteristics of total 270 consequent rock slopes under complicated working conditions are investigated by the discrete element method depending on two parameters, structural plane dip angleθand slope angleα. Differentθ and α ranges corresponding to different failure modes are obtained by the statistical method. Moreover, the relationship between the two parameters and the slope stability is attempted based on the shear strength reduction method. The failure mechanism and stability characteristics of consequent rock slopes are revealed. Four deformation and failure modes of consequent rock slopes are proposed according to different deformation and failure characteristics:toe-slip-failure along the structural plane, top-sliding-failure along the structural plane, lower edge uplift bending-shear failure, and upper edge fracturing-fold-bending-failure. Further general rules of the four modes are analyzed and summarized such as occurrences, deformation characteristics and possible failure modes. The safety factor fs of the slopes decreases and subsequently increases with the increase of θ, it reaches a minimum and then rises quickly to a high value and finally slowing down. During the changing process ofθ, the safety factor fs will obtain a minimum whenθis approximately e-qual to α-7. 3°, which corresponds to the worst slope stability.%针对顺层岩质边坡岩层结构面倾角θ和边坡角α两个参数,采用离散单元法研究了不同工况下总计270个边坡模型的变形破坏特征,统计得到不同变形破坏模式对应的岩层结构面倾角θ与边坡角α的范围,并基于强度折减法研究了两个参数与边坡稳定性的关系,揭示了顺层岩质边坡变形破坏机制及稳定性特征. 研究结果表明:依据边坡变形破坏特征,提出了四种顺层岩质边坡变形破坏模式,即坡脚沿岩层结构面的滑移-剪切破坏,坡顶沿岩层结构面的滑动-剪切破坏,岩层下缘弯曲-剪切破坏,以及岩层上缘翻折-拉裂破坏. 在此基础上,分析并归纳了这四种模式的产状、变形特征以及可能的破坏模式等一般规律. 边坡安全系数fs随结构面倾角θ的增大先减小后增大,在减小过程中达到最小值后迅速上升,然后变缓回落.边坡安全系数fs随结构面倾角θ变化过程中,当θ约等于α-7. 3°时,fs取得最小值,此时对应的边坡稳定性最差.
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