青藏铁路沙害及其防治研究进展

Advances in Research on the Sand Hazards and Its Controls along the Qinghai-Tibet Railway

青藏铁路是中国乃至世界上海拔最高、穿越沙漠冻土的高原铁路。建成以来风沙危害日趋严重,成为危及铁路安全运营的一大隐患,因此,沿线的风沙防治一直备受关注。由于青藏高原风力强劲,沙物质丰富加上人类活动的影响,铁路沙害呈现出分布相对集中,冻融与风力、水力复合侵蚀,不断发展并持续累积,风沙活动稳定性差等特点。沙害分为路基风蚀、道床积沙、磨蚀等类型。累计有轻度、中度、严重沙害路段440km,主要分布在锡铁山、伏沙梁、红梁河、秀水河北麓河、沱沱河、通天河、扎加藏布、错那湖等8个路段。目前铁路沙害防治以机械措施为主,在设置初期有一定的防沙效果,但随着时间的推移,最终会被积沙埋没而失效。因此,青藏铁路防沙应以生物措施(恢复植被)为主,机械措施为辅。

The Qinghai-Tibet Railway （QTR） is the world＇s highest railway across the harshest regions with frozen earth and cold deserts. Ever since it was built up, the railway has been encountering with serious sand hazards. The safe of the operation was also being continuously threatened by the big risk, thus it is in great essential to find an effective way to control the wind-blown sand hazards along the way. Due to the strong wind, rich sand materials and the influence of human activities, the sand hazards along the QTR are characterized by relatively concentrated distribution, compound erosion induced by freeze-thaw, wind and hydraulic power, constantly developing and accumulating degree, and poor stability of blown-sand activities. The sand hazards can be divided into three types such as subgrade deflation, ballast sand deposition and abra- sion. There are about total 440 km of slight, moderate, and severe sand hazards sections distributed mainly at 8 sections along the QTR： Xitie Mountain, Fushaliang, Honglianghe River, Xiushuihe River-Beiluhe Riv- er, Tuotuohe River, Tongtianhe River, Zhajiazangbu River, and Cuonahu Lake. At present, the mechanical control measure is the main method used for protecting the QTR from sand hazards. Although the protection effect is obvious in the initial stages, the way was often be buried by sand sediments eventually. Therefore, we think that biological methods （such as vegetation restoration） would be better if combined with mechani- cal methods for controlling the wind-blown sand hazards along the QTR.