基于AHP-Fuzzy法的灰岩地区崩塌体失稳危险性评价

Hazard Assessment of Collapsed Rock Mass in Limestone Area based on AHP-Fuzzy Method

危岩崩塌体的形成是多种影响因素综合作用的结果,且影响因素具有复杂性与模糊性的特点。基于AHP法,通过分析影响三峡库区灰岩地区崩塌体发育的各种因素,选取地形和地质条件、崩塌体几何特征及其他3个因素作为准则层,遴选出了陡崖高度、陡崖结构特征、陡崖所处地质构造、崩塌体规模、主控结构面倾角、主控结构面贯通度、日最大降雨量、风化作用、地震烈度及人类工程活动等10个评价指标作为子准则层,构成了AHP法的层次结构,建立了危险性评价指标体系。将层次分析法和模糊综合评价法有机结合,构建了三峡库区灰岩地区崩塌体危险性模糊综合评价模型。通过工程实例磨子岩W1,W2,W3三个危岩体对该评价模型进行了检验,磨子岩危岩危险性评价结果符合磨子岩危岩整体稳定性较差,已经发生部分崩塌,危险性极大的客观实际,表明构建的三峡库区灰岩地区崩塌体危险性评价模型具有较好的的适用性。

The formation of collapsed rock mass is the result of the combined action of many influencing factors.These factors are characterized by complexity and ambiguity.Based on AHP method,the factors influencing the development of collapsed rock mass in the limestone area of the three gorges reservoir area are analyzed.Three factors,including topographic and geological conditions,geometric characteristics of the collapsed rock mass and other factors,are selected as the criterion layer.Ten evaluation indexes,such as the height of the escarpments,structural characteristics of escarpments,geological structure of the escarpments,the scale of collapsed rock mass,the dip angle of the main control structural surface,the connectivity of the main control structural surface,daily maximum rainfall,weathering,seismic intensity and human engineering activities,are selected as sub-criteria.The hazard evaluation index system is established.By combining analytic hierarchy process and fuzzy comprehensive evaluation method,the hazard assessment model of collapsed rock mass in the limestone area of the three gorges reservoir area is established.The assessment model was tested by three dangerous rock masses of Moziyan,W1,W2 and W3.The hazard assessment results of moziyan is consistent with the actual situation,the overall stability of moziyan is poor,and part of it has collapsed,which is very dangerous.It shows that the risk assessment model of collapsed rock mass in limestone area of the three gorges reservoir area has good applicability.