水保所知识产出(1956---)知识库

利用室内模拟降雨试验，研究了不同雨强及坡度条件下黄土区土质(不含砾石)与土
石质(砾石质量分数 30%)塿土堆积体的水动力学特征、侵蚀特征及侵蚀动力机制的差异。结
果表明: 砾石存在改变了堆积体坡面的水动力学特性，与土质坡面相比，土石质坡面的流速、
弗汝德数、单位径流功率和过水断面单位能分别减少 1．7% ～ 49．7%、6．7% ～ 60．6%、2．0% ～
44．6%和 1．0%～26．7%;曼宁糙率系数、径流剪切力分别增加 6．2% ～169．4%、5．7% ～79．3%。
2．0、2．5 mm·min
－1
雨强下，土石质坡面侵蚀速率较土质坡面降低 26．2%～89．9%，砾石的减沙
效益显著。2 种堆积体的侵蚀速率与水动力学参数间均可用线性函数拟合，与土质坡面相比，
土石质坡面的可蚀性参数均降低，降幅为 56．1%～73．3%;而临界水动力学参数中径流剪切力
增加 11．1%，径流功率、单位径流功率和过水断面单位能分别减少 25．4%、64．0%和 5．0%。砾
石的存在一定程度上控制了工程堆积体坡面降雨侵蚀过程。

 An indoor rainfall simulation experiment was conducted to examine the hydrodynamic
characteristics，erosion characteristics，and erosion dynamics mechanisms of earth (excluding gra-
vel) and earth-rock (gravel mass fraction 30%) Lou soil engineering accumulation in the Loess area
across different rainfall intensities and slope gradients． Results showed that the presence of gravel
changed the hydrodynamic characteristics of the engineering accumulation slope． The flow velocity，
froude number，unit stream power，and unit energy of water-carrying section of the earth-rock slope
were 1．7%－49．7%，6．7%－60．6%，2．0%－44．6% and 1．0%－26．7% lower than those of the earth
slope，while the Manning roughness coefficient and runoff shear stress of the earth-rock slope were
6．2%－169．4% and 5．7%－79．3% higher than those of the earth slope respectively． Under the inten-
sity of 2．0 and 2．5 mm·min
－1
，erosion rate of the earth-rock slope was 26．2%－89．9% lower than
that of earth slope． The gravel significantly reduced slope erosion of the Lou soil engineering accu-
mulation． Erosion rate and hydrodynamic parameters of the two accumulations were linearly related．
The erodibility parameters of earth-rock slope were 56．1%－73．3% lower than that of earth slope． In
the critical hydrodynamic parameters，runoff shear stress of earth-rock slope was 11．1% higher，
while the stream power，unit stream power and unit energy of water-carrying section were 25．4%，
64．0% and 5．0% lower than those of the earth slope，respectively． The existence of gravel controlledrainfall erosion process on the slope of the engineering accumulation to some extent．