摘要
由于风洞实验室尺寸有限,试验中的桥梁结构需进行缩尺,但目前关于缩尺效应对桥梁涡振风洞试验结果的影响研究较为少见。数值模拟方法可以调节模型尺寸及计算域大小,能够较方便地实现不同缩尺比桥梁断面的涡振计算。针对某大跨度悬索桥结构箱形主梁断面,采用数值模拟方法,开展1∶1、1∶20、1∶50和1∶100四种缩尺比下箱梁的竖向涡振性能研究,对比分析缩尺效应对涡振试验结果的影响。研究表明:缩尺比变化对静止状态箱梁的气动力系数影响较小;随着缩尺倍数的减小,动态升力峰值及波动幅度越大;缩尺模型的涡振振幅小于实桥尺寸下的涡振振幅,且缩尺倍数越大,涡振振幅越小;提出用于修正箱梁涡振试验结果的缩尺效应修正系数,可为桥梁抗风设计提供参考。
Due to the limitation of the size of wind tunnels,the bridge model must be scaled,but few researches have been made on the scale-effects on the vortex-induced vibration(VIV)of the bridge.The model size and calculation domain size can be adjusted when the numerical simulation method is adopted,and the VIV calculation of the bridge section with different scales can be realized conveniently.Based on the numerical simulation method,the vertical VIV performances of the box girder with scale ratios of 1∶1,1∶20,1∶50 and 1∶100 are studied,and the effects of scale ratio on the results of VIV are compared and analyzed.The results show that the variation of the scale ratio has limited effect on the static aerodynamic coefficients of the box girder.The peak value and fluctuation amplitude of vortexinduced lift increase as the scale ratio decreases.The VIV amplitude of the scaled model is smaller than that of the real bridge,and the amplitude decreases with the increase of the scale ratio.The reduced scale effect correction coefficient used to modify the VIV results of the box girder in wind tunnel test is proposed,which can provide reference for wind resistant design of bridge.
作者
陈星宇
徐昕宇
曾永平
郑晓龙
李永乐
CHEN Xingyu;XU Xinyu;ZENG Yongping;ZHENG Xiaolong;LI Yongle(China Railway Eryuan Engineering Group Co.,Ltd.,Chengdu 610031,China;Department of Bridge Engineering,Southwest Jiaotong University,Chengdu 610031,China)
出处
《铁道标准设计》
北大核心
2021年第9期100-104,共5页
Railway Standard Design
基金
国家重点研发计划项目(2017YFB1201204)。
关键词
悬索桥
箱形主梁
涡振
缩尺效应
振幅修正
数值模拟
suspension bridge
box girder
vortex-induced vibration
scale-effects
amplitude correction
numerical simulation
