模拟暴雨条件下植被混凝土坡面侵蚀的水动力学特征

目的] 探究不同外掺料对暴雨条件下植被混凝土坡面侵蚀水动力学特征的影响，在降雨侵蚀方面为植被混凝土的配方改进提供科学依据。方法] 通过室外模拟降雨试验，在60°坡度、3种雨强（60，90，120 mm/h）下研究4种外掺条件（无添加、聚丙烯酰胺、生物炭、棕榈纤维）的植被混凝土坡面侵蚀状况，并分析坡面水动力学参数与土壤侵蚀量之间的关系。结果] 坡面雷诺数始终小于500，坡面流为层流；未添加外掺料的坡面弗劳德数始终小于1，坡面流为缓流，添加外掺料的坡面弗劳德数始终大于1，坡面流为急流。添加外掺料的坡面具有较大的坡面流速、水流功率，较小的水流剪切力、径流深度和阻力系数。添加生物炭的坡面土壤侵蚀量显著高于无添加坡面，添加聚丙烯酰胺和棕榈纤维的坡面土壤侵蚀量显著低于无添加坡面。结论] 外掺料对植被混凝土坡面水动力学参数影响显著。土壤侵蚀量与雷诺数、水流功率呈极显著正相关关系。添加聚丙烯酰胺和棕榈纤维能有效降低植被混凝土边坡土壤侵蚀量，可在高陡边坡生态恢复工作中进行应用。

Hydrodynamic Characteristics in Vegetation Concrete Slope Erosion Under Simulated Rainstorm Experiments

Objective] The influence of different admixtures on the hydrodynamic characteristics of vegetation concrete slope erosion under rainstorm conditions was analyzed to provide a scientific basis for the improvement of vegetation concrete formulations. Methods] The erosion status of vegetation concrete slopes under four admixed conditions (no additives, polyacrylamide, biochar, palm fiber) with 60° slope and three rainfall intensities (60, 90, 120 mm/h) were analyzed by using outdoor simulated rainfall experiments. The relationship between slope hydrodynamic parameters and soil erosion was analyzed. Results] The slope Reynolds number was always less than 500, and the slope flow was laminar. The slope Froude number without admixtures was always less than 1 and the slope flow was slow. The slope Froude number with admixtures was always greater than 1 and the slope flow was rapid. The slope surface with external admixture had a larger slope velocity and water flow power, and smaller water flow shear force, runoff depth, and resistance coefficient. The amount of soil erosion on the slope with biochar addition was significantly higher than without biochar addition. The amount of soil erosion on the slope with addition of polyacrylamide and palm fiber was significantly lower than that without addition. Conclusion] Use of admixtures had a significant effect on the hydrodynamic parameters of a vegetation concrete slope. The amount of soil erosion was very significantly and positively correlated with Reynolds number and water flow power. Adding polyacrylamide and palm fiber can effectively reduce the amount of soil erosion on vegetation concrete slopes, and can be used in the ecological restoration of high and steep slopes.