工程堆积体坡面产流产沙特性的现场试验

通过不同流量(35,45,55L/min)、不同坡度(24°,28°,32°)的野外放水冲刷试验,对工程堆积体坡面产流产沙的时空变化特性进行了研究。结果表明,径流强度与放水强度、产沙率密切相关,三者之间呈多元线性相关;坡面径流强度随冲刷时间呈波动式增大趋势;平均含沙量和产沙比均随坡度增大呈先增后减的趋势,峰值出现在坡度为28°时;径流强度和产沙率在冲刷时间为10min时出现第一个峰值;坡面产沙过程呈现产沙率剧增、波动和稳定发展3个阶段;累计产沙量与累计径流量呈线性关系。试验结果可为工程堆积体坡面水土流失预报模型的构建提供验证数据。

Field Experiment on the Characteristics of Runoff and Sediment Yield on Slopesof Engineering Accumulation Body

A field water-scouring experiment was conducted with different flow rates (35 L/min, 45 L/min, 55 L/min) and different slope gradients (24°, 28° and 32°) in order to explore spatial-temporal characteristics of runoff and sediment yield on slopes of engineering accumulation body. The results showed that the runoff intensity was closely related to the intensity of discharge and sediment yield, and multiple linear correlations existed between them. The runoff intensity showed a fluctuated increasing trend with the increase of scouring time. Average sediment amount and sediment yield ratio increased at first and then decreased with the increase of slope gradients, and the peak value appeared when the slope gradient was about 28°.Runoff intensity and sediment yield showed the first peak values at 10 min. The sediment yielding process included3 stages: sediment yield rapidly increase, fluctuated and steadily developed. The cumulative sediment yield showed linear correlation with the cumulative runoff. The experiment results may provide validation data for the prediction model of soil and water loss in the production and construction projects.