西藏波密县古乡沟泥石流模型试验中的模型砂配制

Sediment Sample Preparation for Simulation Experiment of Debris Flow in Guxiang Gully,Tibet

对西藏古乡沟泥石流模型试验中的模型砂配制进行了研究,旨在保证模型试验的合理性和科学性,从而为泥石流灾害防治工程提供可靠的设计依据。通过对泥石流形成区和堆积区样品的粒径分析,根据模型试验的目的和条件,选定模型的几何比尺为1∶100,但模型砂的配制采用泥砂分段模拟法,原型中小于0.1 mm的颗粒不缩小,仍按重量百分比配制;原型中大于0.1 mm的颗粒按相似比尺缩小后用小于0.1 mm模型砂代替。并通过模型样品的选用和粒径组合对泥石流体以及堆积扇的模型砂配制过程进行了详细的分析研究,使模型试验获得了比较好的结果。

This paper is contributed to the sediment sample preparations for simulation experiment of debris flow in Guxiang Gully,Tibet.According to samples from the source areas and deposit areas of debris flow,the geometrical ratio is chosen as 1∶100.The preparation is made separately in different domains of grain size.Grains smaller than 0.1 mm is used as the original composition while grains bigger than 0.1 mm are placed by the model grains smaller than 0.1 mm according to the model ratio.Combinations of the sediment models and their size distributions are analyzed in details,and the result is satisfactory.