气动措施抑制桥梁涡振机理研究  

Vortex resonance depression mechanism of a bridge deck with aerodynamic measures

作　　者：许福友[1,2] 林志兴[3] 李永宁[3] 楼文娟[1] 

机构地区：[1]浙江大学建筑工程学院,杭州310027 [2]大连理工大学土木水利学院,大连116024 [3]同济大学土木工程防灾国家重点实验室,上海200092

出　　处：《振动与冲击》2010年第1期73-76,共4页Journal of Vibration and Shock

基　　金：国家自然科学基金(50708012);高等学校博士点新教师基金(20070141073);辽宁省博士启动基金(20081086)

摘　　要：通过表面测压方法研究了桥梁主梁基本断面、添加抑流板或导流板后断面的涡激共振特性;基于三种断面不同风速各测点压力时程,综合对比分析脉动压力系数均值、标准差、功率谱及局部与总体气动力相关性对涡振的影响,揭示了扭转涡振及气动措施抑振的机理。研究发现:扭转涡振的根本原因是上表面上游的分离使得中游和下游区域压力脉动非常强烈,各测点脉动压力具有相同卓越频率,且与总体气动力具有良好的相关性;抑流板改善了上表面流场分布,有效抑制了涡振;而导流板对上表面流场基本无影响,未能抑制涡振。The vortex vibration characteristics of one bridge deck with airflow-suppressing board,and guide vane and without any aerodynamic measures were investigated using the surface pressure measuring method.Based on three sections pressure time histories at different wind velocities,the means,standard deviations,power spectra of fluctuated pressures,as well as the correlations between local and total aerodynamic forces were comprehensively analyzed,and the tosional vortex mechanism and aerodynamic measure suppressing mechanism were disclosed.It revealed that severe fluctuation of pressure in the middle and downstream regions at the upper face constructs the fundamental momentum for vortex resonance,which are incurred due to the flow separation at the front upper face;the fluctuated pressures keep the same dominant frequencies;and the local aerodynamic forces keep good correlations with the total ones;the flow distribution at the upper face is adjusted and improved by using the airflow-suppressing board,and the vortex resonance is effectively suppressed;for the negligible influence on flow fields at upper face,the guide vane is ineffective.

关 键 词：涡振 气动措施 抑振 表面测压 涡振机理 

分 类 号：U448[建筑科学—桥梁与隧道工程]