摘要
为研究稳定板对桥面安装带式输送机的边主梁斜拉桥涡振(vortex induced vibration,VIV)性能影响的机理,通过节段模型测压试验获取边主梁表面压力时程,综合对比分析不同稳定板工况下断面脉动压力系数均值、标准差、功率谱、局部与总体气动力的相关性,并揭示下稳定板对边主梁桥的抑振机理。研究发现:该类型主梁竖弯涡激共振发生的原因为上表面前部分离与再附区域强烈的压力脉动,下表面前部气动力与总体气动力的强相关性及后部具有明显相关性的强烈的压力脉动;梁底布置一道稳定板能显著降低断面压力脉动,布置两道稳定板断面压力脉动进一步降低,从而大幅抑制涡振;梁底布置三道稳定板促进了气流在下游风嘴处的再附,断面压力脉动被大幅削弱,局部气动力与总体气动力相关性被显著破坏,从而有效抑制涡振。
In order to study the mechanism of the effect of a stabilizing plate on vortex induced vibration(VIV)performance of a side girder cable-stayed bridge with a belt conveyor installed on the bridge deck,the pressure time-histories date of the edge girder was obtained through a section model pressure test.The mean value of the pressure coefficient,standard deviation,the power spectrum,and the correlation between local aerodynamic force,and overall aerodynamic force of the cross-section on different number of lower stabilizers were comprehensively compared and analyzed,which reveals the vibration suppression mechanism of the edge girder by lower stabilizers.The research results indicate that the causes of the vertical VIV resonance are the strong pressure fluctuation in the front separation and reattachment area of the upper surface,the strong correlation between the front aerodynamic force and the overall aerodynamic force of the lower surface,and the strong pressure fluctuation of the strong correlation in the rear part of the lower surface.Arranging a stabilizer in the bottom of the beam can significantly reduce pressure fluctuation,and arranging two stabilizers can further reduce the pressure fluctuation,which can greatly suppress VIV.Three stabilizers arranged at the bottom of beam promote the reattachment of airflow at the downstream faring,the cross-section pressure fluctuation is greatly weakened,and the correlation between the local aerodynamic force and the overall aerodynamic force is significantly destroyed,the VIV is thus suppressed effectively.
作者
李春光
颜虎斌
梁爱鸿
韩艳
周旭辉
LI Chunguang;YAN Hubin;LIANG Aihong;HAN Yan;ZHOU Xuhui(School of Civil Engineering,Changsha University of Science&Technology,Changsha 410114,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2022年第8期25-33,共9页
Journal of Vibration and Shock
基金
湖南省自然科学基金(2020JJ14607)
国家自然科学基金(51978087,51822803)。
关键词
边主梁
桥面输送机
下稳定板
表面测压
风洞试验
涡振(VIV)机理
edge girder
deck conveyor
lower stabilizer
surface pressure
wind tunnel test
mechanism of vortex-induced vibration(VIV)
