The 2D limit equilibrium method is widely used for slope stability analysis. However, with the advancement of dump engineering, composite slopes often exhibit significant 3D mechanical effects. Consequently, it is of significant importance to develop an effective 3D stability calculation method for composite slopes to enhance the design and stability control of open-pit slope engineering. Using the composite slope formed by the mining stope and inner dump in Baiyinhua No. 1 and No. 2 open-pit coal mine as a case study, this research investigates the failure mode of composite slopes and establishes spatial shape equations for the sliding mass. By integrating the shear resistance and sliding force of each row of microstrip columns onto the bottom surface of the strip corresponding to the main sliding surface, a novel 2D equivalent physical and mechanical parameters analysis method for the strips on the main sliding surface of 3D sliding masses is proposed. Subsequently, a comprehensive 3D stability calculation method for composite slopes is developed, and the quantitative relationship between the coordinated development distance and its 3D stability coefficients is examined. The analysis reveals that the failure mode of the composite slope is characterized by cutting-bedding sliding, with the arc serving as the side interface and the weak layer as the bottom interface, while the destabilization mechanism primarily involves shear failure. The spatial form equation of the sliding mass comprises an ellipsoid and weak plane equation. The analysis revealed that when the coordinated development distance is 1500 m, the error rate between the 3D stability calculation result and the 2D stability calculation result of the composite slope is less than 8%, thereby verifying the proposed analytical method of equivalent physical and mechanical parameters and the 3D stability calculation method for composite slopes. Furthermore, the 3D stability coefficient of the composite slope exhibits an exponential correlation with the coordinated development distance, with the coefficient gradually decreasing as the coordinated development distance increases. These findings provide a theoretical guideline for designing similar slope shape parameters and conducting stability analysis.

中文翻译：

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相邻露天矿采场与内排土场形成的高大型复合边坡三维稳定性计算方法


二维极限平衡法广泛应用于边坡稳定性分析。然而，随着垃圾场工程的进步，复合边坡经常表现出显着的3D力学效应。因此，开发有效的复合边坡三维稳定性计算方法对于加强露天边坡工程的设计和稳定性控制具有重要意义。以白银花一、二露天煤矿采空场和内排土场形成的复合边坡为例，研究复合边坡的破坏模式，建立滑动体的空间形状方程。通过将每排微带柱的剪切力和滑动力积分到主滑动面对应的条带底面上，提出了一种新颖的3D滑动体主滑动面上的条带2D等效物理力学参数分析方法被提议。随后，建立了复合边坡综合三维稳定性计算方法，并检验了协调发育距离与其三维稳定性系数之间的定量关系。分析表明，复合边坡的破坏模式为切层滑动，以圆弧为侧界面，软弱层为底界面，失稳机制以剪切破坏为主。滑动质量的空间形式方程包括椭球方程和弱平面方程。 分析表明，当协调发展距离为1500 m时，复合边坡3维稳定性计算结果与2维稳定性计算结果误差率小于8%，从而验证了所提出的等效物理力学参数分析方法。以及复合边坡的三维稳定性计算方法。此外，复合边坡的三维稳定性系数与协调发展距离呈指数相关，随着协调发展距离的增加，该系数逐渐减小。这些发现为设计类似的坡形参数和进行稳定性分析提供了理论指导。