Abstract: Debris flow is a kind of destructive natural disasters, and how to scientifically evaluate its influence factor and risk degree is very important. Aiming at “8.13” catastrophic debris flow at Qingping township in Mianzhu, the fuzzy comprehensive evaluation method and the maximum membership principle were used to determine the final evaluation results in the process of debris flow risk assessment. And then, taking evaluation results as decision attributes and impact factors as condition attributes, the debris flow risk assessment model was established, combined with rough set and decision tree theory. The results show that the main factors affecting the debris flow in Qingping township are the largest output of the debris flow and the residual solid loose material. At the same time, the risk assessment of debris flow can be completed quickly through the proposed model and the evaluation results are in agreement with the actual situation, which shows that using rough set and decision tree theory to evaluate the risk of debris flow is feasible.

Key words: geotechnical engineering, debris flow, evaluation model, fuzzy comprehensive evaluation method, decision tree

摘要： 泥石流作为一种破坏性极大的自然灾害，如何科学地评价其影响因子和危险程度显得尤为重要。针对绵竹市清平乡“8.13”特大泥石流灾害，在泥石流危险性评价过程中，采用模糊综 合评判法并根据最大隶属度原则确定最后评价结果。然后以评价结果作为决策属性，影响因子作为条件属性，结合粗糙集和决策树理论构建泥石流危险性评价模型。结果表明：影响清平乡泥 石流最主要的因素为最大冲出量和剩余固体松散物质，同时通过该模型能快速完成泥石流灾害的危险性评价，评价结果与实际情况吻合，表明将粗糙集和决策树理论用于泥石流危险性评价是 切实可行的。

关键词: 岩土工程, 泥石流, 评价模型, 模糊综合评判法, 决策树