水保所知识产出(1956---)知识库

        为室内试验中更好地模拟工程堆积体，利用图像分析法和经典统计学方法对六大典型水蚀区的368座工程堆积体中粒径D＞1 cm的坡面砾石的分布和含量进行概化分析，得到工程堆积体下垫面上中下坡位砾石含量的概化区间。结果表明：工程堆积体坡面各粒径砾石含量大多服从正态分布，且山区和平原丘陵区之间的砾石总含量有显著性差异。工程堆积体坡面砾石重力分选作用明显，且随着砾石粒径的增加，分选程度增大。在室内进行工程堆积体下垫面设计时，山区堆积体的砾石总含量宜设置在50%~60%之间，其中，细粒砾石含量宜设置在20%~30%之间，中粒砾石含量宜设置在10%~15%之间，粗粒砾石和巨粒砾石含量宜设置为10%，堆积体上中下坡位坡面砾石含量配比宜设置为1∶1.3∶1.5；平原丘陵区的砾石总含量宜设置在15%~20%之间，其中细粒砾石、中粒砾石、粗粒砾石、巨粒砾石含量分别宜设置在5%~10%、3%~7%、2%~5%、2%~3%之间，堆积体上中下坡位坡面砾石含量配比宜设置为1∶1.5∶2.5。

        In order to simulating underlying surface of engineering accumulation, using image analysis and classical statistics methods to generalize the distribution and content of the gravel whose diameter are greater than 1 cm on 368 engineering accumulation slopes which are located in six water erosion region. We can get the generalized content interval of gravel which distributed on different slope position. The results show as follows: Most gravel of different particle diameter obey normal distribution and there is a significant different in the content of gravel in mountain areas or in plain-hilly areas. The gravels’gravity separation effects are obvious, and the bigger the gravel is, the more remarkable the effects are. In mountain areas, it's appropriate to set the total amount of gravel at the percent between 50% to 60% when we design the spoil underlying surface for laboratory rainfall simulation; the content of fine gravel, medium grained gravel, coarse grained gravel and macrosome gravel are set to the range of 20% to 30%, 10% to 15%, 10% and 10%; the content of gravel on top, middle and bottom slope of engineering accumulation are suggested to be 1:1.3:1.5. In hilly and plain areas, it's appropriate to set the total amount of gravel at the percent between 15% to 20%, while the fine gravel, medium grained gravel, coarse grained gravel, macrosome gravel accounting for 5%～10%, 3%～7%, 2%～5%, 2%～3% respectively. The proportion of gravel on top, middle and bottom slope of engineering accumulation is best set at 1:1.5:2.5.