摘要
为研究复杂交通状态下车桥系统的气动特性,对某大跨度公铁两用桁架斜拉桥进行了节段模型风洞试验。测试了不同风攻角下单列车、两列车、三列车通过时车桥系统的三分力。研究了线路位置、桥塔、公路车流、双车及三车交会对车辆和桁梁三分力系数的影响。结果表明:当单列车从迎风侧线路向背风侧线路移动时,车辆和桁梁的阻力系数逐渐减小,但车辆的升力系数及桁梁的力矩系数在背风侧轨道达到最大;当列车通过桥塔,受遮挡车辆的平均表面风压会显著减小,当其位于迎风侧轨道时影响最明显,但在靠近桥塔边缘处的表面风压波动较为剧烈;双车交会时,车辆的阻力和升力系数随交会间距的增大而增大;三车交会时,位于迎风侧列车后方的车辆阻力和升力系数显著下降,中间车的升力系数最小且阻力系数为负数;随着桥上列车数量的增加,桁梁的阻力和升力系数逐渐增大,而力矩系数基本保持不变。
To investigate the aerodynamic characteristics of train-bridge systems in a complex traffic condition, a section model wind tunnel test was carried out for a long-span rail-cum-road cable-stayed truss bridge. The tricomponent forces on the train-bridge system were measured under different angles of attack when a single train,two trains or three trains passed. The effects of the track positions, bridge towers, road traffic flows, meeting of the trains on the tri-component coefficients of the vehicle and the truss were studied. The results show that when a train moves from the windward track to the leeward, the drag coefficients of the vehicle and the truss gradually decrease, while the lift coefficient of the vehicle and the moment coefficient of the truss reach the maximum on the leeward track. As a train passes through the tower, the average surface wind pressure of the shielded vehicle is significantly reduced, and the shielding effect is most obvious when it is on the windward track. However, the surface wind pressure near the tower edges remarkably fluctuates. When two trains meet on the bridge, the drag and lift coefficients of the vehicle increase with the meeting spacing. When three trains meet on the bridge, the drag and lift coefficients of the vehicles behind the windward train significantly decrease. The middle train has the s mallest lift coefficient and a negative drag coefficient. As the number of trains on the bridge increases, the drag and lift coefficients of the truss gradually increase, while the moment coefficient remains almost the same.
作者
郭薇薇
蔡保硕
娄亚烽
张慧彬
GUO Wei-wei;CAI Bao-shuo;LOU Ya-feng;ZHANG Hui-bin(School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China)
出处
《工程力学》
EI
CSCD
北大核心
2021年第3期192-201,共10页
Engineering Mechanics
基金
国家自然科学基金面上项目(51878036)。
关键词
车桥系统
大跨度公铁两用桁架斜拉桥
气动特性
节段模型
风洞实验
train-bridge system
long span rail-cum-road cable-stayed truss bridge
aerodynamic characteristic
section model
wind tunnel test
