| In this paper, with Zhunger-shuozhou railway as an example, we have conducted a research on the sand damage to railway through field observation, primarily focusing on the laws of wind erosion in the reformed topographical area of railway construction sites. Our study leads to the following conclusions:(1) The construction of embankments and cutting excavations can accelerate or decelerate the wind's speed on the surface, which might cause erosion and siltation.(2) The sediment discharge rate varies with height. At various locations the wind speed and the sediment volume have a power function relationship. Its relation is Q= AVB,Q is the sediment volume (g/m2·min), V is the wind speed (m/s), A,B representative the constants.(3) The sediment discharge rate of embankments, cutting excavations, dumping sites, and pioneer roads below 30cm-high is approximately 80%, indicating that the sediment volume within these areas mainly accumulates within 30cm beneath the surface.(4) The leeward slope and windward slope of embankments and cutting excavations have the similar wind-drift sand structure. The structural eigenvalue of dumping sites should be higher than one, which is conducive to siltation, whereas that of the pioneer road should be lower than one, which is conducive to erosion.(5) The annual erosion amount of dumping sites and pioneer roads is relatively large, ranging from 3000 t/km2 to 4000 t/km2, whereas that of embankments and cutting excavations is between 1500 t/km2 and 2700 t/km2.(6) According to field observation and measurement, the comprehensive prevention measures combining engineering method and biological method can not only effectively reduce the sediment volume caused by wind erosion and the wind speed near the surface, but also are conducive to the encrustation of the ground surface.
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