基于SPR与DEMATEL模型的村域山洪灾害危险评价

Hazard assessment of village-level mountain torrent disaster based on SPR and DEMATEL model

为提高山洪危险性评价的准确度和实际应用价值,以巫山县大溪乡官田村作为村域尺度山洪灾害危险评价的研究区域,以土地利用类型作为评价单元,根据单元间的拓扑邻接关系,构建官田村2D-SPR山洪灾害危险评价概念模型。选取糙率、高程、单元间中心距离和单元间边界长度构建表征山洪洪水流量的指标体系,并利用TOPSIS多属性决策工具,计算基于流量指标的单元间相互影响强度。结合DEMATEL算法,计算各单元影响度、被影响度,考虑大溪河溢出和未溢出堤岸两种情景,完成村域尺度山洪危险评价。结果表明无论是否发生漫堤式洪灾,研究区各单元危险性指数排序均为S3>11>5>S2>6>7>10>8>S4>12>9>4>3>13>14>2>1,且随着洪水强度增加危险性指数增大。

This paper takes Guantian Village,Daxi Township,Wushan County,as the research area,and the types of land use as the assessment unit to improve the accuracy and practical value of hazard assessment of torrential flood.A conceptual model of 2D-SPR mountain flood hazard assessment is constructed based on the topological adjacency relationship between units.In the conceptual mode,such indexes as roughness,elevation,center distance and boundary length between units are selected to characterize the mountain flood discharge.In addition,the TOPSIS multi-attribute decision-making tool is used to calculate the intensity of interaction between units based on flow index.Combining with the DEMATEL complex network model,this paper also calculates the degree of influence and degree of the affect in each unit.A village-scale mountain flood hazard assessment is finally completed on the basis of these calculations and the two scenarios of Daxi River overflow and non-overflow embankment.It is demonstrated that the hazard indexes in each unit are sequenced as S3>11>5>S2>6>7>10>8>S4>12>9>4>3>13>14>2>1 whether the flood poses the risk of breaking the dam and such hazard index will increment with the increase of the water flood intensity.