摘要
对某高100 m的菱形截面纪念碑进行刚性模型多点同步扫描测压与摆式气弹模型测振风洞试验,进而在测压数据基础上建立频域风荷载模型并采用随机振动分析方法计算结构风振响应,同时应用随机减量技术(RDT)识别了该气弹模型风致振动时的气动阻尼比。当在频响函数中考虑气动阻尼比后的风振响应计算结果和气弹模型试验值具有很好的一致性。由于实际结构振型与摆式模型线性振型存在差异,用振型修正系数修正气弹模型试验结果可得到实际结构风振响应。分析结果表明,刚性模型测压建立荷载模型,结合气弹模型测振识别气动阻尼,代入实际结构频域响应计算方法能够较精确地评估强风作用下低频小阻尼高耸结构的风致气弹响应。
Wind tunnel tests of surface pressure scanning with a rigid model and vibration measurement with a stick-like aero-elastic model for a 100-meter-high monument with diamond-shaped cross-section were conducted,and then its frequency domain wind load model was established based on the pressure measurement data and the wind-induced response of the structure was calculated with the method of random vibration theory.Meanwhile,the aerodynamic damping ratio were identified by applying the random decrement technique （RDT）.When the aerodynamic damping ratios were considered in the structural complex frequency response function,the calculation results of the wind-induced dynamic responses agreed well with the aero-elastic model test ones.Due to the difference between the structural actual modal shape and the linear modal shape of the stick-like aero-elastic model,modal shape correction factors were adopted to modify the aero-elastic model test results,and then the actual structural responses were acquired.The analysis results showed that the frequency domain response analysis method of a actual high-rise structure with a wind load model established using the surface pressure scanning test of a rigid model,combined with an aerodynamic damping identification using the aero-elastic model vibration measurement test,can be used to accurately assess the wind-induced aero-elastic responses of high-rise structures with low frequency small damping under strong wind actions.
出处
《振动与冲击》
EI
CSCD
北大核心
2014年第8期88-95,共8页
Journal of Vibration and Shock
基金
国家自然科学基金项目(50678137)
关键词
纪念碑
摆式气弹模型
风致气弹响应
气动阻尼比
线性振型
monument
stick-like aero-elastic model
wind induced aero-elastic response
aerodynamic damping ratio
linear modal shape
