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泥石流最大冲出总量是泥石流防灾减灾工程设计中的重要参数。汶川地震后泥石流物源条件发生了很大变化,灾害活动频率增高,暴发点多,规模增大,现有公式难以准确估算震后泥石流最大冲出总量。对灾区的44条泥石流沟进行了回归分析发现:由于震区的泥石流多为土力类,在20年一遇的暴雨袭击下,灾区泥石流沟的最大冲出总量与沟道内松散物质储量之间存在很强的幂函数关系。物源的储量和性质对冲出总量起着决定性的影响,降雨特征和流域形态也对泥石流冲出总量有一定影响。不同面积的泥石流沟对降雨的响应不同,主要由降雨能否提供足够的水动力条件决定。流域的微地貌变化造成洪峰流量和冲出总量较预测值偏大。降雨频率越大,流域内固体物质启动越多,冲出总量越大。近矩形流域的泥石流沟面积和冲出总量的线性关系明显,而近扇形流域则不存在线性关系。
Debris flow out of the total amount of debris flow disaster prevention and mitigation project design an important parameter. After the Wenchuan earthquake, the source conditions of debris flow have undergone great changes, the frequency of disasters has increased, the outbreaks have increased and the scale has been increased. It is difficult to accurately estimate the maximum outflow of debris flow after the earthquake with the existing formula. The regression analysis of 44 debris flow ditches in the disaster area shows that due to the earthquakes in the earthquake area are mostly earth-mined, under the heavy rain hit in 20 years, the total outflow of debris flow ditches in the disaster area and the loose material reserves in the channel There is a strong power function relationship between. The reserves and nature of the provenance play a decisive role in the total amount of hedging. The characteristics of rainfall and the morphology of the watershed also have an impact on the total amount of debris flow out. Different area of the debris flow ditch response to different rainfall, mainly by the rainfall can provide adequate hydrodynamic conditions. The micro-topography of the basin caused the flood peak flow and out of the total amount is larger than the predicted value. The larger the rainfall frequency is, the more solid material will be activated in the basin and the larger the total amount will be washed out. The linear relationship between the area of debris flow gully and the total amount of outflow in the near rectangular river basin is obvious, but there is no linear relationship in the near-fan basin.