摘要
以兰新高铁沿线穿越的烟墩风区为背景,基于现场试验和数值模拟,进行风沙流结构特征和挡风墙周围积沙特征研究。结果表明:兰新高铁烟墩风区风沙流携沙量随高度呈负指数分布,且沙粒主要以细沙为主,中沙次之,粗沙最少;挡风墙迎风侧、正上方、背风侧分别处于气流减速区、加速区和紊流区;挡风墙与上行线之间的风速廓线随高度呈先增大后减小的趋势,上行线中心线处呈先增大后减小再增大的趋势,但下行线变化幅度明显大于上行线;风沙流的携沙量一定时,随着风速的增大,挡风墙迎风侧积沙量逐渐减少,背风侧积沙量逐渐增大,且积沙分布区域逐渐向下行线转移;风速一定时,随着风沙流携沙量的增大,沉积在挡风墙两侧的积沙量呈递增趋势;线路沙害主要原因是既有积沙的2次转移,需及时清理挡风墙与上行线之间的积沙。
Based on field tests and numerical simulation, the characteristics of wind-sand flow structure and aeolian sand around windbreak wall were studied under the background of Yandun wind zone crossed by Lanzhou-Xinjiang high speed railway. Results show that the sand carrying capacity of wind-sand flow in Yandun wind zone along Lanzhou-Xinjiang high speed railway shows a negative exponential distribution with height, and the sand particles are mainly fine sand, followed by medium sand and the least coarse sand. The windward side, right above side and leeward side of the windbreak wall is located respectively in the deceleration, acceleration and turbulence zones of the airflow. The wind speed profile between the windbreak wall and the uplink first increases and then decreases with the height. At the center line of the uplink, it increases first, then decreases and then increases, but the change range of the downlink is obviously larger than that of the uplink. When the sand carrying capacity of wind-sand flow is constant, the aeolian sand amount at the windward side and the leeward side of windbreak wall decreases and increases gradually with the increase of wind speed, respectively, and the distribution area of aeolian sand gradually shifts to the downlink. When the wind speed is constant, the aeolian sand at both sides of the windbreak wall shows an increasing trend with the increase of sand carrying capacity of wind-sand flow. The main cause for the sand damage on the line is the two transfers of the existing aeolian sand, so the aeolian sand between the windbreak wall and the uplink should be cleared in time.
作者
韩峰
石龙
李凯崇
HAN Feng;SHI Long;LI Kaichong(School of Civil Engineering, Lanzhou Jiaotong University, Lanzhou Gansu 730070, China;School of Civil Engineering, Southwest Jiaotong University, Chengdu Sichuan 610031, China;Northwest Research Institute Co. Ltd. of C.R.E.C., Lanzhou Gansu 730000, China)
出处
《中国铁道科学》
EI
CAS
CSCD
北大核心
2019年第5期9-15,共7页
China Railway Science
基金
国家自然科学基金地区基金项目(51568037)
中国中铁股份有限公司科技开发计划课题(2015-KJ035-G004-03)
中国铁路总公司科研试验任务书(Z2014-034)
关键词
兰新高铁
风区
风沙流
响应规律
挡风墙
Lanzhou-Xinjiang high speed railway
Wind zone
Wind-sand flow
Response law
Windbreak wall
