基于最优组合赋权和模糊综合评价法的杂谷脑河下游泥石流危险性评价

Application of optimal combined weights method and fuzzy comprehensive evaluation method in risk evaluation of the debris flow along the downstream of Zagu river

基于模糊集理论,综合层次分析法、熵值法的优缺点,利用最优赋权法对评价因子赋权,最大程度考虑主客观因素在权重计算中所占的比重,建立泥石流模糊综合评价模型。以杂谷脑河下游20条泥石流沟为例,选取泥石流最大冲出量、流域面积、主沟长度等7个因子构成评价集,利用模糊综合评价模型,对该区泥石流进行危险性评价。将评价结果与刘希林单沟泥石流危险性评价法比较,三岔沟和曾头沟的模糊综合评价危险等级高于单沟泥石流危险评价结果,其余泥石流沟评价结果相同。评价结果与实际情况吻合,表明利用最优组合赋权法的模糊综合评价是合理可行的。

Based on fuzzy set theory and advantages and disadvantages of the analytic hierarchy process and entropy value method, a model on fuzzy comprehensive evaluation of debris flow is established to calculate the weight of every evaluating factor by using the optimal combined weights method and considering furthest the subjective and objective factors in the proportion of weight calculation. With taking the 20 debris flow along the Zagu river downstream for example, choosing 7 factors such as, the maximum volume of a debris flow, basin area, the length of main gully and so on, the model on fuzzy comprehensive evaluation is adopted to estimate the risk of the 20 debris flow gullies. The evaluation results are compared with the results of single gully debris flow harazd assessment by LIU Xilin. The risk degrees of the Sancha gully and Zengtou gully using the fuzzy comprehensive evaluation method are greater than the resuits of single gully debris flow harazd assessment, and the others are the same, which is coincided with the filed investigation. The results suggest that the optimal combined weights method combining with fuzzy comprehensive evaluation method in the debris flow risk assessment is feasible.