环状结构横风向风振响应分析
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罗楠，廖海黎，李明水（西南交通大学风工程试验研究中心， 成都 610031）［摘要］高层建筑横风向风振响应备受风工程和结构工程领域的关注，其横风向振动主要是旋涡脱落下的涡激共振。主要介绍某环状结构横风向涡激共振的形成和影响因素。对于这种特殊结构，无法直接由规范查到斯特罗哈数，因而不能判定实际结构发生横风向涡激共振的起振风速。通过气弹模型试验获得结构的涡振起振风速，并测试了各个风向角下结构顶部的加速度响应，把试验结果换算到实际结构，分析了横风向涡激共振的影响因素。试验结果表明：对于此类结构，影响最大的是风向角，其次是结构的阻尼比和来流的紊流度。因而建议此类结构在建造时使其易于发生横向风振的方位避免与主风向垂直。［关键词］环状结构； 涡激共振； 气弹模型； 风向角中图分类号：TU312+.1，TU973.2+13 文献标识码：A 文章编号：1002-848X(2013)08-0032-04Analysis on across windinduced dynamic responses for a ring structureLuo Nan, Liao Haili, Li Mingshui(Research Centre for Wind Engineering, Southwest Jiaotong University, Chengdu 610031, China)Abstract: Across wind-induced dynamic responses on tall buildings, which is mainly caused by vortex-induced vibration, are drawn much attention in the fields of wind engineering and structure engineering. The formation and influencing factors of vortex-induced vibration for a ring structure were introduced. Specifications do not provide the Strouhal number for this particular structure, so the start-up wind velocity of across vortex-induced vibration can not be determined. In this study, the start-up wind velocity of vortex-induced vibration was obtained by the aeroelastic model test and acceleration responses in cases of various wind directions were investigated. Then test results were applied in the real structure to analyze the influencing factors of across vortex-induced vibration. The results demonstrate that the wind direction has greatest impact on vortex-induced vibration for the ring structure, while the damping ratio of the structure and the turbulence intensity of the flow have smaller impact. Therefore, the situation that the position of ring structures is perpendicular to the main wind direction should be avoided.Keywords: ring structure; vortex-induced vibration; aeroelastic model; wind direction参考文献［1］洪小健,顾明.顺风向等效风荷载及响应——主要国家建筑风荷载规范比较［J］. 建筑结构, 2004,34(7):39-43.［2］张相庭.结构顺风向风振的规范表达式及有关问题的分析［J］. 建筑结构, 2004,34(7):33-35.［3］KWOK K C S, MELBOURNE W H. Wind-induced lock-in excitation of tall structures［J］. Journal of the Structural Division, 1981, 107 (ST1):65-82.［4］KAREEM A. Fluctuating wind loads on buildings［J］. Journal of the Engineering Mechanics Division, 1982, 108（6）:1086-1102.［5］赵文钦.圆形截面高耸构筑物的横向风振研究［J］.西安冶金建筑学院学报,1983,33(1):1-27.［6］梁枢果,夏法宝,邹良浩，等.矩形高层建筑横风向风振响应简化计算［J］.建筑结构学报,2004, 25(5): 48-54.［7］蒋洪平,张相庭.变截面高耸结构的横向风振研究［J］.振动与冲击,1994, 49(1):46-54.［8］WILLIAMSON C H K, GOVARDHAN R. Vortex-induced vibrations［J］. Annual Review of Fluid Mechanics,2004, 36（1）:413-455.［9］LIE H, KAASEN K E. Modal analysis of measurements from a large-scale VIV model test of a riser in linearly sheared flow［J］. Journal of Fluids and Structures,2006, 22（4）: 557-575.［10］GB 50009—2001建筑结构荷载规范［S］. 2006年版. 北京:中国建筑工业出版社,2006.［11］黄本才,汪丛军.结构抗风分析原理及应用［M］.上海:同济大学出版社,2008.［12］SARPKAYA T. A critical review of the intrinsic nature of vortex-induced vibrations［J］. Journal of Fluids and Structures,2004,19（4）: 389-447.
