基于熵权法和聚类分析的泥石流群危险度评价研究

Risk Assessment of Debris Flow Clusters based on Entropy Weighting Method and Cluster Analysis

泥石流的发生会破坏基础设施以及威胁人的生命财产安全,特别是在风景名胜区,因此对泥石流进行危险度评价研究就显得尤为重要。以四川彭州龙门山镇的14条泥石流为研究对象,在现场地质调查的基础上,结合无人机影像、多幅遥感影像综合确定各泥石流的基本特征,选取流域切割密度、圆度、主沟道平均坡度、流域最大高差、主沟床弯曲系数、泥砂补给段长度比、植被覆盖率、人口密度、单位面积物源量共9个因子作为影响泥石流危险度的主要指标,采用熵权法确定各指标的权重、熵值及不同泥石流的综合评价得分值,同时利用量子粒子群优化算法对AP聚类算法进行改进,并以熵权法计算结果为基础,采用改进后的AP聚类算法对龙门山镇14条泥石流进行分类,引入聚类有效性指标判断泥石流分类效果,提出研究区范围内泥石流危险度的量化标准,最终对研究区14条泥石流做出危险度评价。将评价结果与灰色关联法、耦合协同法及现场调查结果进行对比,证明本文提出方法是可行的,也为其他地区相关问题的研究提供了合理的科学依据。

The occurrence of debris flows can damage infrastructure and threaten human life and property safety,especially in scenic places.Therefore,it is particularly important to classify and evaluate the risk of debris flows.In the paper,14 debris flow gullies in Longmenshan Town,Pengzhou,Sichuan are taken as the research object.Based on on-site geological surveys,combined with drone images and multiple remote sensing images,the basic characteristics of each debris flow gully are comprehensively determined.The watershed cutting density,roundness,average slope of the main channel,maximum height difference of the watershed,bending coefficient of the main channel bed,length ratio of mud and sand supply section,vegetation coverage,population density,and material source quantity per unit area,a total of 9 factors are taken as the main indicators affecting the risk degree of debris flow.The entropy weight method is used to determine the weight and entropy value of each indicator and the comprehensive evaluation score of different debris flow gullies.At the same time,the quantum particle swarm optimization is used to improve the AP clustering algorithm.Based on the calculation results of the entropy weight method,the improved AP clustering algorithm is used to classify 14 debris flow gullies in Longmenshan Town,clustering effectiveness indicators are brought to assess the effectiveness of debris flow classification,quantitative standards for the risk of debris flow within the study area are proposed,and finally,the risk of debris flow in the study area is evaluated.The evaluation results are compared with those of the grey correlation method,coupled collaboration method,and on-site investigation results,proving that the method proposed in this paper is feasible and can provide a reasonable scientific basis for research on related issues in other regions.