坡面薄层水流侵蚀试验研究及土壤抗冲性评价  

Experimental research on sheet flow erosion of loessial slope and evaluation on soil anti-scourability

作　　者：雷俊山[1] 杨勤科[1] 

机构地区：[1]中国科学院水利部水土保持研究所,陕西杨凌712100

出　　处：《泥沙研究》2004年第6期22-26,共5页Journal of Sediment Research

基　　金：中科院知识创新重要方向项目"黄土高原水土保持的区域环境效应研究"(KZCX3_SW_42 1)

摘　　要：通过室内冲刷试验 ,研究了坡面薄层水流的水力学参数特征及产沙变化 ,结果表明 ,粒径的雷诺数和弗汝得数都随放水流量而增大 ,但其流型和流态仍保持不变。径流流速 ,产沙率均随着流量的增大而呈幂函数增大 ,阻力系数则随着雷诺数的增大呈幂函数减小。分析薄层水流下理想坡面土壤颗粒的受力情况得出坡面产沙与径流剪切力关系的概念模型。结合试验数据 ,确定出模型参数的值 ,并得出试验土壤的临界切应力。The hydraulics characteristic of sheet flow and the sediment in the process of slope erosion have been studied through indoor scouring experiments in this paper. The results show that both the Reynolds number and the Froude number increase with the discharge, but the type of the state of the sheet flow remains the same. It is also found that the flow velocity and the sediment yield increase exponentially with the discharge but the Daycy_weisach coefficient decreases exponentially with the increment of the Reynolds number. Analyzing the stresses of the soil grain on the ideal slope produces a conceptive model. According to the experimental data, both the parameter of the model and the critical shear stress of the soil were deduced.

关 键 词：土壤抗冲性 径流剪切力 临界剪切力 

分 类 号：S157.1[农业科学—土壤学]