黄土道路侵蚀过程模拟试验研究

黄土地区土质道路侵蚀强烈,严重影响当地的生产与交通事业。开展黄土道路侵蚀研究,对于黄土地区水土保持与生态经济建设具有重要意义。采用模拟降雨试验方法研究了黄土道路侵蚀过程,取得了如下结果。(1)道路径流侵蚀发生时间随雨强及坡度的变化皆可用幂函数方程描述;(2)道路径流侵蚀开始时含沙量很高,但很快下降并随降雨历时的延长而逐渐趋于相对稳定;(3)道路侵蚀率变化过程可分为3个阶段:径流侵蚀开始至20min及40min至侵蚀过程结束,侵蚀率随降雨过程的变化较大,20～40min之间基本稳定;(4)道路侵蚀模数随雨强及坡度的变化均可用幂函数方程描述,雨强及坡度对道路侵蚀的综合影响可用二元线性方程描述。

Experiment Modeling of Soil Erosion Processes on Loess Roads Based on Simulated Experiment

Road erosion in the loess region is a severe problem which influences traffic,transportation and agricultural activities etc.Research on road erosion is very important to soil and water conservation,ecology construction and economy development in the region.Based on simulated rainfall experiments,erosion processes on loess roads are studied,and following results are obtained.(1)The variations of starting time of soil erosion by runoff with rainfall intensity and slope gradient can be respectively described with exponential equations.(2)The sediment concentration is very high in the initial stage of soil erosion processes by runoff on road.However,the concentration decreases very quickly,and then gradually becomes relative steady in continued rainfall processes.(3)The variation of road erosion rate can be divided into three stages during which the variation of erosion rate with rainfall process is great from the commence of soil erosion by runoff to 20 min,and from 40 min to the end of runoff erosion processes,and is relatively steady from 20 min to 40 min.(4)The variations of road erosion modulus with rainfall intensity and slope gradient can be described with exponential equations,respectively,and the integrated effects of rainfall intensity and slope gradient on road erosion can be described with a binary linear equation.