摘要
为研究紊流风场中桥梁颤振性能,针对紊流积分尺度对桥梁颤振导数的影响,选取了高宽比为1∶6的钝体矩形及流线型箱梁两种典型断面,采用变化被动格栅网格间距及格栅位置的方式,模拟产生了具有相同积分尺度不同紊流强度以及相同紊流强度不同积分尺度的4种紊流风场。利用强迫振动装置测试了4种紊流场中两种断面节段模型的颤振导数变化规律,并与均匀流场试验值进行了对比。试验结果表明,钝体矩形断面受紊流风场影响显著,尤其与颤振稳定性密切相关的扭转振动气动阻尼项A*_2,H*_2由正向负衰减显著,改善了断面的颤振稳定性,且随紊流强度增加衰减加剧,积分尺度对其影响较弱。各颤振导数受积分尺度影响不尽相同,部分导数对积分尺度变化不敏感。紊流风场对流线型断面的各项颤振导数影响较小,相比均匀流场试验值未显示趋势性改变。
In order to study the flutter performance of bridge in turbulence flow, aiming at the effect of turbulence integral scale on bridge flutter derivatives, selecting the typical deck sections of streamlined box girder and bluff rectangular girder with high-width ratio of 1：6 , and using the size and position of changeable passive grid, 4 turbulence fields, which have same integral scale but different turbulence intensities or the same turbulence intensity but different turbulence integral scales, are generated. The variations of the flutter derivatives of 2 kinds of section models in the 4 kinds of turbulence field are tested by means of forced vibration device, and the test values are compared with those of the uniform flow field. The result shows that （1） the bluff rectangular section affected by the turbulent wind field significantly, especially the torsion aerodynamic damping derivatives A^＋2 and H^＋2 which are closely related to the flutter stability decayed from positive to negative significantly, and the sectional flutter stability is improved, the attenuation increases with the increase of turbulence intensity, however, the integral scale has little influence on the derivatives A^＋2 and H^＋2 ; （2） the turbulence integral scale have different effect on each of the flutter derivatives, part of them are not sensitive to the change of integral scale; （ 3 ） the flutter derivatives of streamline box girder section fell little impact from the turbulent wind field, compared with the test result in uniform flow, the flutter derivatives in turbulence do not exhibit trend of change.
出处
《公路交通科技》
CAS
CSCD
北大核心
2016年第11期69-75,共7页
Journal of Highway and Transportation Research and Development
基金
国家重点基础研究发展计划(九七三计划)项目(2015CB057706)
国家自然科学基金项目(51208067,51478049)
交通建设科技项目(2011318824140)
湖南省重点学科创新项目(2013ZDXK05)
关键词
桥梁工程
颤振导数
强迫振动
积分尺度
被动格栅紊流
bridge engineering
flutter derivative
forced vibration
integral scale
turbulence of passive grid
