基于改进的FAHP-CRITIC法与云理论的露天矿边坡危险性评估模型

Risk assessment model of open-pit mine slope based on improved FAHP-CRITIC method and cloud theory

针对传统评估方法无法同时解决露天矿边坡危险性评估中存在的不确定性和模糊性问题,提出了基于改进FAHP-CRITIC法博弈赋权与正态云模型的边坡危险性评估方法。选取地质、工程、水文条件等多方面因素构建综合评价指标体系,首先采用改进FAHP法和CRITIC法分别确定主、客观权重;进而通过博弈论模型确定最优综合权重;然后结合云模型计算各指标的不同等级隶属度,求出不同边坡隶属于不同危险等级的综合确定度,由最大隶属度原则划分边坡的危险性等级。将该模型运用于某露天铜矿边坡危险性评估,其评估结果与实际情况相符,表明该方法是科学可行的,并与其他方法的评估结果进行对比分析,分析结果进一步证明了该评估模型的可靠性。

Aiming at the uncertainty and fuzziness existing in the slope risk assessment of open-pit mine,this paper constructs a weight determination method based on the Improved Fuzzy Analytic Hierarchy Process(FAHP)-the Criteria Importance Through Intercrieria Correlation(CRITIC) method,and then puts forward the slope risk assessment method based on the normal cloud theory.The selected 11 evaluation indexes are analyzed,including the rock quality,rock mass structure characteristic,cohesive force,internal friction angle,ground stress,high density,slope height,slope,average annual rainfall,earthquake intensity,and human activity.The above 11 evaluation indexes are chosen from five aspects in geological environmental characteristics,hydrological factors,engineering conditions,slope geometries.The risk grades of slope in the combination of the above indicators are divided into five levels:extremely low risk,low risk,higher risk,high risk,and very high risk.Firstly,we respectively adopt the improved FAHP method and the CRITIC method to determine the subjective and objective weights of each evaluation index,then employ the game theory to find a balance between the subjective and objective weights,determining the optimal comprehensive weights of each index.Meanwhile,the forward cloud generator of the cloud model is used to calculate the membership degree of each finger grade of each slope that needs to be evaluated according to the cloud digital characteristics calculated in the paper.Based on the optimal comprehensive weights and grade membership degree of each index obtained above,the comprehensive determination degree of each slope to be evaluated can be calculated.Finally,according to the maximum certainty principle,the risk grade of the slope is divided.The model is applied to assess the risk of three slopes of an open-pit copper mine.Fortunately,the assessment results are consistent with the reality,namely grade II,grade III,and grade V,indicating the accuracy and feasibility of the assessment model.Compared with the results of other methods,the analysis further proves that the evaluation model mentioned above is scientific and feasible,and can be applied to the slope risk assessment of open-pit mine.