和田—若羌铁路戈壁盐碱区高立式“Z”字形沙障配置的风洞试验

Wind Tunnel Experimental Study on Actual Setup of Upright Z-Shaped Sand Barriers in Gobi Saline Zone Along Hetian-Ruoqiang Railway

[目的]探究多排“Z”字形沙障的合理配置模式,为和田—若羌铁路沿线戈壁盐碱区的风沙防护提供科学参考。[方法]在风洞中模拟当地的风沙环境,对孔隙率为40%的多排“Z”字形高立式沙障的防沙效果进行试验。[结果]多排沙障的迎风面与风向的夹角为钝角时,沙障后积沙出现分离现象;沙障的迎风面与风向的夹角为锐角时,沙障后积沙出现聚集现象。防沙效率随着风速增加都有所下降,当风速为12 m/s(7级风)时,设置两道高立式沙障和三道高立式沙障的防沙效率分别为74.0%和100%,当风速增加至15 m/s(9级风)时,设置两道高立式沙障和三道高立式沙障的防沙效率分别为72.7%,88.9%。[结论]鉴于该研究区风沙条件,建议采用三道沙障,沙障的迎风面与风向尽量呈钝角布置。

[Objective]The reasonable configuration pattern of multi-row Z-shaped sand barriers was studied in order to provide a reference for wind and sand protection in the gobi saline-alkaline area along the Hetian-Ruoqiang Railway(HRR).[Methods]Experiments were carried out in a wind tunnel to simulate the local blown-sand environment and to test the sand-control effect of multiple rows of Z-shaped upright sand barriers with a porosity of 40%.[Results]Sand accumulation behind the folded corner of the sand barrier was separated when the angle between the face of sand barrier and the wind direction was an obtuse angle.Sand accumulation behind the folded corner of the sand barrier was aggregated when the angle between the face of the sand barrier and the wind direction was an acute angle.The sand prevention efficiency of two and three high vertical sand barriers decreased with increasing wind speed.When the wind speed was 12 m/s(level 7 wind),the sand prevention efficiency of two and three high vertical sand barriers were 74.0%and 100%respectively.When the wind speed increased to 15 m/s(level 9 wind),the respective sand prevention values were 72.7%and 88.9%.[Conclusion]It is recommended that three sand barriers should be used,with the windward side of the barriers positioned at an obtuse angle to the wind direction as far as possible.