摘要
当平行双幅桥的两个主梁距离较近时,双幅桥面之间的气动干扰效应对颤振性能具有不利的影响。为提高平行双幅桥的颤振稳定性,基于一座平行双幅Π型断面斜拉桥,开展了间距比(D/B)、风嘴角度和竖向稳定板以及水平分离板等多种气动措施下节段模型风洞试验,分析了这些工况下的颤振临界风速和颤振导数的变化规律。结果表明,气动干扰效应对于双幅桥的颤振稳定性都具有不利的影响,其中该效应对上风侧桥的影响小于下风侧桥,对闭口截面的影响要小于开口截面,随着间距比的增大而逐步减小;此外,65°风嘴时的颤振稳定性最好,上中央和下四分点的竖向稳定板均可减小气动干扰效应,而水平分离板反之。
When the distance between two main girders of a parallel twin-separate bridge becomes small,the aerodynamic interference effect between the surfaces of the twin-separate bridge has a harmful influence on its flutter performance.In order to improve the flutter stability of a long-span twin-separate bridge,some effective aerodynamic control measures were employed due to the poor aerodynamic performance of the deck form.A two-separate bridge with Ⅱ Shaped deck was taken as an example to conduct a series of wind tunnel tests of the section model,the change laws of flutter critical wind speed and aerodynamic derivatives for a twin-separate parallel bridge under many different aerodynamic measures including different spacing ratio,wind fairing,vertical stabilizing plate and horizontal splitting plate were analyzed.Results showed that aerodynamic interference effect is harmful to the flutter stability of the two-separate bridge,the influences of aerodynamic interference effect on the windward deck are smaller than those on the leeward deck,and the effects on the closed deck are smaller than those on the opened deck,the effects decrease gradually with increase in spacing ratio; the bridge with the fairing angle of 65 has the best flutter stability,and all vertical stabilizing plates with the below quartile point and the up-central point can improve the flutter performance while horizontal splitting plates have the opposite effects.
出处
《振动与冲击》
EI
CSCD
北大核心
2014年第12期126-132,共7页
Journal of Vibration and Shock
基金
科技部国家重点基础研究计划(973计划)
(2013CB036300)
国家自然科学基金资助项目(51078276
91015013)
交通行业重点实验室自主课题(KLWRBMT-04)
国家重点实验室自主课题(SLDRCE 10-B-05)
关键词
平行双幅桥
颤振稳定性
气动控制措施
气动干扰效应
气动干扰因子
twin-separate parallel bridges
flutter stability
aerodynamic control measures
aerodynamic interference effect
aerodynamic interference factor
