坡面水土流失比尺模型相似性的试验研究  

Laboratory Rainfall Simulations for Similarity Criterion of Scale Model on Interrill Erosion

作　　者：徐向舟[1] 张红武[1] 张羽[1] 张德昌[1] 

机构地区：[1]清华大学水利水电工程系,北京100084

出　　处：《水土保持学报》2005年第1期25-27,31,共4页Journal of Soil and Water Conservation

基　　金：国家自然科学青年基金项目(40201008);全国优秀博士论文作者专项基金资助项目(199935)

摘　　要：通过不同比尺的系列模型试验,为坡面水土流失的比尺模型相似性研究,提供了原型和模型的降雨-产沙资料。试验结果表明,坡面产沙浓度随时间的变化有较强的紊动性,因此建议采用经验回归的方法率定降雨产沙的比尺关系;原型和模型的侵蚀产沙量都与雨强成幂函数相关,其雨强系数随模型几何比尺的增大而减小,而雨强指数的大小与坡面几何尺度的大小无关。This study involves a laboratory rainfall simulation to design scale model experiments of soil erosion on the interrill. A net-styled downward-spraying rainfall simulator generated laboratory rainstorms of 1.0~4.0 mm/min with raindrop characteristics approaching those of natural rainfall and a series of test troughs containing a reconstructed tilled loess with saturated water was used to evaluate the interrill erosion. In some events of the experiments, rainstorms of known intensity and duration were applied to the test trough and the ensuring sediment-runoff water mixture was collected with results expressed as erosion quantity. In other experiments, the mixture, from each certain period, was analyzed with results expressed as sediment concentrations and runoff. As a result, sediment concentrations varied acutely as time went on though the runoff from the slope kept stable, and dry weights of sediment from the slopes were approximately proportional to a power function of rainfall intensity.

关 键 词：坡面产沙 水土流失 侵蚀产沙量 降雨 浓度 试验结果 雨强 紊动 模型试验 率定 

分 类 号：S157[农业科学—土壤学]