基于无人机倾斜摄影技术的公路路基两侧积沙变化及沙害特征研究

Research on the Changes of Sand Accumulation and Sand Hazard Characteristics on Both Sides of Highway Sub-grade Based on UAV Tilt Photography Technology

沙漠地区风沙运动频繁,极易对线路造成沙害。为研究沙漠腹地线路的沙害影响,本文选取乌玛高速公路腾格里沙漠腹地路基试验段,借助无人机倾斜摄影技术,提取路基两侧积沙高程数据,结合沿线气象站的风况资料,研究路基两侧不同沙丘距离、高度等条件下的积沙变化,进而对沙害特征进行分析研究。结果表明:(1)远沙丘路基迎风侧积沙在秋季减少,其他季节逐渐增加,夏季延伸至路面;背风侧在夏季减少,其他季节缓慢增加。(2)远沙丘路基沙害为迎风侧沙埋,沙丘高度和沙地坡度越大,沙埋现象越严重,沙地坡度对沙埋影响效果更显著。(3)近沙丘路基两侧,夏秋两季积沙增加,春冬两季沙丘在吹蚀过程中往东南方向移动。(4)近沙丘路基沙害为迎风侧沙埋,夏季风沙流饱和后的沙埋要远大于春冬两季沙丘移动产生的沙埋,沙丘高度越小,迎风侧坡度越大,沙埋情况越严重。

The frequent sand movements in desert areas are very likely to cause sand damage to the line.In order to study the impact of sand damage on the desert hinterland line,the sub-grade test section in the Tengger Desert hinterland of the Uma Expressway is selected,the sand elevation data on both sides of the sub-grade is extracted with the help of UAV tilt photography technology,and combined with the wind condition data from the weather stations along the route,the changes of sand accumulation on both sides of the sub-grade under the conditions of different distances and heights of dunes are studied,and then the characteristics of sand damage are discussed.The results show that:(1)The sand accumulation on the windward side of the far dune sub-grade decreases in autumn and increases in other seasons,extending to the road surface in summer;the leeward side decreases in summer and slowly increases in other seasons.(2)The sand hazard on the far dune sub-grade is sand burial on the windward side.The greater the height of the dune and the slope of the sand,the more serious the sand burial effect,and the slope of the sand has a more significant effect on the sand burial.(3)Both sides of the sub-grade near the sand dunes,the sand accumulation increases in summer and autumn,and the dunes move to the southeast during the erosion process in spring and winter.(4)The sand hazard of the sub-grade near the dunes is the sand burial on the windward side.The sand burial after the saturation of the wind and sand flow in summer is much larger than that caused by the movement of the dunes in spring and winter.The smaller the height of the dune and the greater the slope of the windward side,the more serious the sand-burial effect.