近年来,弃渣型泥石流灾害时有发生。为了探索弃渣型泥石流输沙速率,以陕西省小秦岭金矿区的大西岔沟为研究背景,对大西岔沟泥石流的孕灾条件和成灾特征进行了详细的野外调查,发现该区域地形陡峻,弃渣总储量丰富,具备良好的泥石流孕灾条件。同时,泥石流在沿程运动和演化过程中,将具有明显的沿程放大和链生特征。结合野外调查资料,理论推导了弃渣型泥石流输沙速率的计算方法,并根据相似准则设计了水槽模型试验,对计算理论中的冲刷系数进行了率定。试验数据表明冲刷系数的取值范围在3.2×10^-5~7.1×10^-5 m·s/kg之间。这些率定参数将用于后续的小流域泥石流产汇流过程研究之中,同时也为该区域其他相关研究以及泥石流监测预警提供科学参考。

In recent years, debris flow induced by mine waste broke out frequently. With Daxicha gully in the gold mine area of Shaanxi Province as a background, we conducted detailed field investigations on the hazard-inducing conditions and formation conditions of debris flow and found that the study area is of sufficient hazard-inducing conditions with steep terrain and abundant storage of mine waste. Moreover, the debris flow amplifies and develops chain effects along the way. On the basis of filed investigation data, we deduced with the calculation formula of sediment discharge rate, and then set up a flume experiment in accordance with similarity criterion to calibrate the scouring coefficient obtained by the formula. According to model test data, the scouring coefficient varied from 3.2×10^-5 to 7.1×10^-5 m. s/kg. Finally, the calibrated parameters can be used in researching the processes of runoff yield and concentration of debris flow in small watershed, and also offer reference for the monitoring and early-warning of debris flow.