Discussion on On-Way Distribution Regulation of Slop Runoff Shear Stress and Its Influencing Factors

摘要

By outdoor stimulation experiments of slope runoff scouring, the on-way distribution regulation of slope runoff shear stress and its influencing factors were studied. In the experiments, different conditions were stimulated, including three levels of grass coverage (bare slope: 0%, low level: 30%-40%, high level: 70%-80%), slopes of four gradients(15°, 20°, 25°, 30°), and three levels of discharge(3L/min, 5L/min, 8L/min). The results showed that the slope runoff shear stress was directly proportional to scouring discharge, but inversely proportional to grass coverage, it was also greatly influenced by the plot gradients, but the relationship was complicated. The value of slope runoff shear stress fluctuated on different on-way sections, besides, the fluctuation range and the initial fluctuation section both differed as conditions changed, including grass coverage, discharge and gradients. Provided high level of discharge and low coverage, the fluctuation range would be large and had a high frequency.