熵权物元可拓模型在泥石流危险性评价中的应用

Application of entropy-weight and matter-element extension model in hazard assessment for debris flow

根据各因素对泥石流系统的贡献程度,选取对泥石流活动具有重要影响的8项指标——一次最大可能冲出量、发生频率、流域面积、主沟长度、最大相对高差、流域切割密度、泥沙补给长度比、24h最大降雨量——作为危险度评价因子,并在物元可拓理论、关联函数运算的基础上,建立多指标评价的物元可拓模型.为避免人为因素的干扰,运用熵权法确定各因子的权重,并参照泥石流危险度等级划分标准,以云南东川地区的7条泥石流沟为具体实例,予以危险度评价分析.结果表明,基于熵权物元可拓模型的泥石流危险度评价具有客观准确、简洁易行的优势,该模型的使用为泥石流危险度评价问题提供了一种新的解决途径.

The assessment system was composed of 8indexes,including one-time runout volume,frequency of occurrence,drainage area,length of main channel,maximum relative altitude in drainage area,incising density,length proportion of debris supplement section,maximum rainfall in 24 hours according to the contribution rate to the debris system,which have great effects on debris flow.On the basis of matter-element＇s extension theory and the formula for incidence function,those indexes were used to establish the matter-element model as assessment factors.And the weight of each factor was calculated by the entropy-weight method to avoid man-made subjective errors.The improved model has obtained a satisfying result by analyzing the practical example of debris flow in Dongchuan city,according to the grade standard of debris flow risk and the predecessor＇s research results.The model has the advantage of objectivity,accuracy,concision,simple operation,and provide an alternative method of risk assessment of debris flows.