公路两侧沙丘粒度特征分析——以榆商高速神木县锦界镇路段为例

Granulometric analysis of dunes along both sides of highspeed——A case study of the road segment of Yushang highspeed in Jinjie of Shenmu

选取榆商高速神木县锦界镇路段两侧紧邻公路的沙丘和距离公路较远未经人为扰动的原始沙丘,采集沙丘表层沉积物进行粒度特征分析.结果表明,S20高速公路锦界镇路段两侧沙丘以中沙和粗沙为主,其次为细沙,极粗沙和粉沙含量都很少.公路西北侧沙丘平均粒径略大于东南侧,分选系数均较好,两侧沙丘的偏度均为负偏,峰度主要为中等型.公路建设改变了局地近地表气流发展,使得高速路两侧风速增大,并且呈现从西北向东南风速逐渐减小的规律,进而导致两侧沙丘表层沉积物粒径分布出现明显差异.

5 dunes and 55 sand samples were collected in Yushang highway. The results show that themain sand of those dunes are medium sand and coarse sand, followed by fine sand, particularly coarsesand and silt content are very few. The average particle size of dunes in northwest of the highway isslightly coarser than the southeast. On both sides of the dunes, sorting is better. Skewness are negative,kurtosis is mainly medium. Due to the interference of highway, even if under the condition of the samewind, different intensity of wind on either side of the highway, leading the significant differences on bothsides of the dunes surface sediment particle size distribution.