施工期路堤对小流域径流和产沙影响的试验研究

Study on Impacts of Embankment under Construction on Runoff and Sediment Yielding in Small Watershed

通过在退水阶段对施工期铁路路堤所在的小流域径流和产沙的试验研究表明,由于路堤改变了原来小流域部分支沟的径流途径,使得小流域内的径流主要为壤中流和路堤上游洼地积水的渗流所组成。径流规律分析结果表明,其退水过程按对数曲线规律变化。据此分析了路基渗流和施工扰动对小流域产沙的影响,提出预防路堤渗流直接冲刷下游农田的建议。

Based on monitoring of runoff and sediment concentration at water lowing phase in small watershed traversed by an embankment under construction, we discover that embankment can change the original runoff route and the runoff in the watershed is mainly composed of interflow and seepage flow from the water of the low land in the upper reach. The law of runoff is analyzed, the results indicate that the water lowing pattern conforms to logarithmic function. Furthermore, the impacts of the seepage flow through the embankment and the construction disturbance on small watershed sediment yielding are analyzed,the suggestion for preventing seepage flow from directly scouring the land in the lower reach of the embankment is proposed.