贵阳小关桥双肢薄壁墩抖振响应试验与影响因素分析  

Analysis of influence factors of buffeting response and full-scale aeroelastic experiments for the Xiaoguan Bridge

作　　者：韩艳[1,2] 陈政清[2] 王建辉[2] 汪志昊[2] 

机构地区：[1]长沙理工大学,湖南长沙410076 [2]湖南大学,湖南长沙410082

出　　处：《土木工程学报》2009年第1期41-48,共8页China Civil Engineering Journal

基　　金：国家自然科学基金(50478051)

摘　　要：在原有抖振时域分析方法的基础上,提出一种考虑复气动导纳函数的修正和抖振力的空间相关性的抖振时域分析方法。为对现有抖振时域分析方法的验证,以贵阳小关桥为例,对其最大悬臂状态进行全桥气弹模型风洞试验,试验中不仅对抖振位移进行测量,还通过在墩底布设动态应变片完成墩底内力的实测。气动导纳函数分别取1、Sears函数和实测的桥梁断面复气动导纳函数,采用抖振力谱法得到考虑气动导纳修正的抖振力。另外对风洞中模型抖振力的空间相关性进行测量,分析气动导纳函数和抖振力空间相关性对结构抖振响应的影响,并与风洞气弹模型试验结果进行了对比分析。分析结果表明:计算分析结果与试验结果基本一致;采用结构实际气动导纳函数的抖振响应与试验更接近;采用抖振力空间相关性计算得到的抖振响应要比采用脉动风速空间相关性的计算结果偏高。A new time domain method taking into account of modification of complex aerodynamic admittance functions and effect of coherence functions of buffeting forces is presented. Full-scale experiments of the Xiaoguan Bridge are carried out for verification of the buffeting analysis method. The buffeting-induced internal forces at the bottom of the piers as well as the buffeting-induced structural displacements are measured by means of dynamic strain gauges. Aerodynamic admittance functions are, respectively, set as 1, Sears functions and the measured complex aerodynamic admittance functions to simulate the buffeting forces by using the buffeting force spectrum method. Coherence functions of buffeting forces are measured in the wind tunnel. The effects of aerodynamic admittance function and coherence functions of buffeting forces on buffeting response are analyzed, and the analytical results and the experimental results are comparatively analyzed, which show that the analytical results agree well with the experimental results and that the buffeting responses when considering the modification of the measured complex aerodynamic admittance function of the bridge are closer to the experimental results. The results also indicate that the buffeting responses based on the coherence functions of buffeting forces are greater than the buffeting responses based on the coherence functions of wind turbulence.

关 键 词：桥梁结构 抖振时域分析 气动导纳函数 抖振力空间相关性 风洞试验 

分 类 号：U448.23[建筑科学—桥梁与隧道工程]