乌玛高速公路穿沙试验段风况特征及流场分布规律  

Wind Regime Characteristics and Flow Field Distribution in Sand-crossing Test Section of Wuhai-Maqin Expressway

作　　者：刘志博 韩峰[2] 李良英[2] 尹文华[2,3] 倪国庆 LIU Zhi-bo;HAN Feng;LI Liang-ying;YIN Wen-hua;NI Guo-qing(China Railway Design Corporation,Tianjin 300308,China;School of Civil Engineering,Lanzhou Jiaotong University,Lanzhou Gansu 730070,China;Ningxia Highway Survey and Design Institute Co.,Ltd.,Yinchuan Ningxia 750001,China)

机构地区：[1]中国铁路设计集团有限公司,天津300308 [2]兰州交通大学土木工程学院,甘肃兰州730070 [3]宁夏公路勘察设计院有限责任公司,宁夏银川750001

出　　处：《公路交通科技》2024年第1期62-70,共9页Journal of Highway and Transportation Research and Development

基　　金：国家自然科学基金项目(51568037);宁夏交通运输厅科技项目(20200173)。

摘　　要：为探究乌玛高速公路穿沙段风沙活动规律,明晰道路周围风力环境与积沙形成机理,从而为道路提供科学防沙依据,在腾格里沙漠腹地乌玛高速正线附近修建一条长0.5 km的无防护同向试验段公路,通过现场试验量测并辅以计算流体力学(CFD)数值模拟,在分析风动力环境特征的基础上,对路基周围风沙流场结构及积沙规律进行研究。结果表明:(1)道路区段内风向受季节影响较大,年均起沙风速约为6.26 m/s,主导风向WSW方向,占比11.03%,观测期间风速5 m/s以上起沙日数270 d,占全年日数73%,其中风速大于10.8 m/s的强风天气为47 d,占全年日数13.1%。(2)试验区全年沙物质主要由西向东方向输移,春季和夏季输沙环境最强烈,所测风沙流主方向与道路走向呈52°夹角,道路沿线沙害主要发生在西侧。(3)路基周围风速流场内水平速度呈“M”状变化,最大风速集中在沙丘顶部,当沙丘处于道路迎风侧时,风沙流最易在路基与沙丘交界处形成积沙,且沙丘会沿主风向移动掩埋路基;当沙丘处于道路背风侧时,路基背风侧积沙较明显,受多风向影响,路基表面也存在少量积沙,模拟结果与现场观测具有较好的一致性。强劲的风力环境和丰富的沙源是乌玛高速沙害形成的天然条件,防沙工程应着重对沿线西侧设置,增大地表粗糙度控制沙丘流动,进而降低风沙活动对公路危害。In order to study the rule of blown sand activity in the sand-crossing section of Wuhai-Maqin expressway,to clarify the wind environment around the road and the formation mechanism of sand accumulation,so as to provide a scientific sand-prevention basis for road system,a 0.5 km unprotected test road in the same direction is built near the main line of Uma expressway in the hinterland of Tengger Desert.Based on the analysis on the characteristics of wind dynamic environment,the structure of blown sand flow field and the rule of sand accumulation around the roadbed are studied by field experimental measurement and computational fluid dynamics(CFD)numerical simulation.The result shows that(1)The wind direction in the road section is greatly affected by the season.The average annual sand threshold velocity is about 6.26 m/s,and the dominant wind direction is WSW,which is accounting for 11.03%.During the observation period,the number of sand-driving days with wind speed above 5 m/s is 270 d,which is accounting for 73%of the annual number of days,and the number of strong wind days with wind speed greater than 10.8 m/s is 47 d,which is accounting for 13.1%of the annual number of days.(2)The sand transport in the experimental area is mainly from west to east throughout the year with the strongest sandtransport environment in spring and summer.The main direction of blown sand flow is 52°with the direction of road,and the sand hazard along the road mainly occurs in the west.(3)The horizontal velocity of wind flow field around the roadbed changes in the M-shaped,and the maximum wind speed is concentrated at the top of the dune.When the dune is on the windward side of the road,the sand flow is most likely to form sand at the junction of the roadbed and the dune,and the dune will move along the main wind direction and bury the roadbed.When the dune is on the leeward side of the road,the sand accumulates obviously on the leeward side of the roadbed.Strong wind environment and abundant sand sources are the natural conditions f

关 键 词：道路工程 公路沙害 流体模拟 风沙活动 流场分布 

分 类 号：U418.56[交通运输工程—道路与铁道工程]