【摘要】 松潘县地坪沟属于发展期的低频暴雨型泥石流沟,在"5.12"汶川特大地震后该流域内由于崩塌滑坡造成的松散堆积物储量增多,泥石流发生频率有增高的趋势,危险性变大。在应用层次分析法(AHP),选择泥沙补给长度比(C1)、流域面积(C2)、主沟长度(C3)、流域相对高差(C4)、主沟平均比降(C5)、流域切割密度(C6)、松散固体物质储量(C7)、主沟弯曲系数(C8)、形成区山坡平均坡度(C9)、一次泥石流最大冲出量(C10)、泥石流暴发频率(C11)、最大24h降雨量(C12)、植被覆盖率(C13)和人口密度(C14)作为评价指标的基础上,运用泥石流沟危险度评价模型计算出地坪沟泥石流危险度为52.64,属于中等偏高危险;同时,又选择刘希林1996年提出的单沟泥石流危险度评价方法进行验证,计算出地坪沟泥石流危险度为0.5563,属于中度偏高度危险,与AHP法评价结果基本吻合,同时与实际勘察结果有较好的一致性。该结果可为当地的泥石流防灾减灾以及预测预报工作提供一定的理论指导。更多还原

【Abstract】 The Diping gully is a developmental period of low-frequency storm-type debris flow.After the"5.12" Wenchuan earthquake,landslides and other loose deposits have increased in the basin.The frequency of debris flow is becoming high.Using the analytic hierarchy process(AHP),length of sediment supply ratio(C1),drainage area(C2),main channel length(C3),basin relative height(C4),average than the main channel lower(C5),basin cut density(C6),loose solid material reserves(C7),main groove bending coefficient(C8),average slope gradient-forming region(C9),maximum out of a debris flow volume(C10),debris flow frequency(C11),maximum 24h precipitation(C12),vegetation coverage(C13) and population density(C14) were chosen as evaluation indexes.The risk degree of Diping gully was calculated as 52.64 with the risk assessment model of debris flow.The risk grade of Diping gully was belong to medium risk.Furthermore,it is verified with other risk assessment methods(Liu Xilin’s,1996),and the result was subordinate to high risk.These two results were basically with the practice.Therefore,it can provide some theoretical guidance to debris flow prevention and prediction for the local government.更多还原