基于主客观综合赋权-正向云模型的露天矿含软弱岩层组高陡复杂边坡稳定性分级评定

Stability of High and Steep Slope of Weak Rock Formation in Open Pit Mine Based on Subjective and Objective Comprehensive Weight-forward Cloud Model

露天矿含软弱岩层组边坡作为工程中常见的特殊地质边坡,在工程实践中具有较一般类型边坡更大的危险性和复杂性。为克服该类型特殊地质边坡稳定性评定过程中的模糊性,保证边坡稳定性安全评价结果的可信度,基于层次分析法的思想,针对含软弱岩层组边坡创建带量化等级区间的稳定性评价指标体系,运用模糊层次分析法(FAHP)和改进熵权法(Entropy)相融合的主客观综合赋权法,并结合正向云理论构建露天矿含软弱层组高陡边坡稳定性辨识标准云模型图。以某金属露天矿为例,生成露天矿含软弱层组高陡边坡稳定性评价实际云图,通过Dice系数计算实际云图与标准云模型图各等级的相似度,对露天矿含软弱层组高陡边坡稳定性进行评定。结果表明:该露天矿含软弱层组高陡边坡稳定性评价实际云图与标准云图对比各等级相似度分别为{0.0127,0.4284,0.7832,0.2043},由最大相似度准则确定该边坡处于不稳定状态(C等级),与数值模拟、传统极限平衡法分析结果基本一致,验证该模型具有一定的科学性和有效性。该研究为含软弱岩层组边坡建立具有针对性的不确定性分析方法,为其它类似特殊地质边坡稳定性的分析和防治提供思路和手段。

Open-pit mines commonly feature soft rock layers as slope components,which pose a greater danger and complexity compared to general slope types in engineering.To address the ambiguity in stability research of these special geological slopes and ensure reliable results for stability safety evaluation,this study adopts the Analytical Hierarchy Process(AHP) to establish a quantified grade interval-based stability evaluation index system specifically designed for slopes with soft rock layers.It utilizes a combination of fuzzy AHP and an improved entropy weight method to derive a comprehensive weighting method that incorporates both subjective and objective factors.Additionally,cloud theory is employed to construct a cloud model diagram representing the stability identification standards for high-slope slopes with soft rock layers in open-pit mines.Taking an open-pit mine as an example,the actual cloud map for evaluating the stability of the open-pit high and steep slope was generated,and the similarity between the actual cloud map and the modified cloud map was calculated by using the Dice algorithm to evaluate the stability of the open-pit high and steep slope.The results show that the similarity between the actual cloud map and the modified cloud map for the total evaluation of the stability is {0.0127,0.4284,0.7832,0.2043}.The slope stability is unstable(Grade C),which is basically consistent with the analysis results of numerical simulation and the analysis results of the traditional limit equilibrium method,verifying that the model is scientific and effective to a certain extent.The study presents a targeted uncertainty analysis method for slopes with weak rock formations and it provides ideas and means for other similar complex slope stability analysis and prevention.