临潼大水沟泥石流特征分析及危险性评价

Features Analysis and Hazard Assessment of Dashuigou Debris Flow in Lintong

研究目的:大水沟位于西安临潼区,大水沟泥石流是典型暴雨型泥石流。以其实测资料为基础,分析其流域特征、成因特征,选用合理的经验公式确定其主要特征值。在此基础上,建立一简捷、实用的泥石流危险性评价模型,模型应用权的最小平方法来确定评价因子权重,确保了权值的准确性。泥石流危险性模型的建立可为泥石流预测预报以及防治工程提供依据。研究结论:研究结果表明选用流域最大相对高差、泥石流可能发生规模、泥石流发生频率、流域面积、主沟长度、主沟平均比降、影响区人口密度、24 h最大降雨量、泥砂补给段长度比等9个因子作为泥石流危险性评价因子是合理、可行的。利用模型对大水沟泥石流的危险性进行评价,结果为高危险。评价结果与大水沟泥石流的危害现状及活动趋势非常吻合。证明该模型用于泥石流危险性评价是有效和可行的,具有一定的理论和现实意义。

Research purposes： Dashuigou is located in Lintong where there is a typical rainstorm debris flows.Based on the measured data,this paper analyzes the watershed features and genesis of Dashuigou debris flow to select the reasonable empirical formuls to determine avalues of its main features.On this basis,a simple and practical hazard assessment model of debris flow is established.The minimum square method for the appied weight of model was used to determine the factor weight to ensure the accuracy of the weights.The establishment of hazard assessment model can provide the basis for predicting the disasters of debris flow and taking the control measures for the disaster.Research conclusions：The research result indicates that using the maximum relative altitude in drainage area,the scale of potential debris flow,debris flow frequency,drainage area,length of main ditches,the average slope of main ditches,maximum rainfall in 24 hours,population density and length proportion of debris supplement section to assess the debris flow hazard is reasonable and feasible.Dashuigou debris flow was assessed with this model.The result showed the Dashuigou debris flow was of high-hazard and it was consistent with the real hazards status and activities trend.So the model for debris flow hazard assessment is effective and feasible with certain theoretical and practical significance.