山区高速公路弃土场形态研究及区域差异分析

Highway Waste Dump Shape and Regional Differences in Mountain Areas

公路弃土场水土流失是公路建设水土流失的重要组成部分,弃土场的形态决定了其侵蚀特点,因而对公路弃土场形态的合理评估与模拟是准确预测预报区域内公路弃土场水土流失量的前提。利用公路弃土场堆放的位置及地貌特点,建立了估算区域弃土场形态的方法,并使用常德至张家界高速公路的弃土场的设计资料对该方法进行了检验,最后比较了东南丘陵区与西南山区在修建相同长度公路下所形成的弃土场的特点。结果表明,用该方法所计算的弃土场高度来代替弃土场设计高度的平均相对误差为37.67%,计算高度与设计高度的相关系数为0.94;平均每修建100km公路,东南丘陵区所产生弃土量约为西南山区的2.1倍;相对西南山区,东南丘陵区弃土场呈现出多集中于沟谷,弃土场个体体积较大,高度较低,数量较少的特点。

Soil erosion of soil dump during highway construction is one of the most important parts of road erosion,and the terrain features of the dump determines its erosion characteristics.The evaluation and prediction of the dump shape is therefore the prerequisite for precise soil erosion estimation of the soil dumps.An approach was established to estimate the shapes of soil dumps according to the characteristics of highway excavation and soil piling,and it was then tested with the data obtained on Changde—Zhangjiajie Highway.At last,the regional differences of dump shapes were compared between southwest mountainous areas and southeast of China.The results show that the method well predicted the height of waste dumps,with a mean relative error of 37.67% and correlation coefficient of 0.94.The waste soil production during highway construction in the mountainous areas was 1.5 times more than that in the hilly regions.The waste dumps of the mountainous areas were mainly located in gullies and valleys,with relatively larger volumes and occupancy areas and lower heights.