The mechanism of sand damage at the Fushaliang section of the Liuyuan–Golmud expressway

Abstract

Abstract The Liuyuan–Golmud Expressway is located in the extreme arid area inland of the Hexi Corridor and Qaidam Basin. This expressway, particularly its Fushaliang section, is prone to serious blown sand hazards. The causes of these hazards remain unknown, thereby hindering targeted sand prevention and control. The aim of this paper is investigate the mechanism of sand damage in Fushaliang by performing a field observation of the locale and conducting wind tunnel simulation experiments. Results show that the sand-moving wind in Fushaliang dominates in the northwest west (WNW) direction. The wind speed, sand-moving wind frequency, sand drift potential, and maximum possible sand transport quantity in Fushaliang are high during summer and low during winter, and the yearly resultant sand transport dominates in the southeast east (ESE) direction. The wind route in Fushaliang is approximately perpendicular to the dominant wind and sand transport directions. During summer, sand materials are blown by the wind from WNW to ESE, after which they are blocked by the expressway roadbed. An area with high wind speed is observed at the shoulder of the windward roadbed slope that leads to a blown sand flow erosion. Meanwhile, low wind speed areas are observed –5H at the upwind direction of the roadbed and from the shoulder of the leeward slope of the roadbed to the 15H downwind direction. These areas accumulate sand materials at the up- and down-wind directions and then release them to the leeward slope of the roadbed, thereby resulting in blown sand hazards. The findings of this work can guide the prevention and control of sand damage in this section of the expressway.