大跨屋盖风荷载的频域特性试验研究  

Frequency domain characteristics of wind loads on a long span building roof

作　　者：陈伏彬[1,2] 李秋胜[2,3] 傅继阳[4] 谢壮宁[5] 

机构地区：[1]长沙理工大学土木与建筑学院,长沙410114 [2]湖南大学建筑安全与节能教育部重点实验室,长沙410082 [3]香港城市大学建筑系 [4]暨南大学土木工程系,广州510006 [5]汕头大学土木工程系,广东汕头515063

出　　处：《振动与冲击》2012年第5期111-117,共7页Journal of Vibration and Shock

基　　金：国家自然科学基金资助项目(50578061;506080371);广东省科技计划资助项目(2006B37201011)

摘　　要：在大气边界层风洞中通过模拟大气边界层风场对广州国际会展中心模型进行测压试验,获得了测点的在36个风向角下的风荷载。对风荷载的功率谱、相关系数、相干函数进行了细致分析,讨论了风场对脉动风压频域特性的影响。得出一些结论:脉动风压功率谱表现很强的漩涡脱落特征,其斯脱罗哈数约为0.295;测点风压相关系数横风向强于顺风向,均随着测点间距的增大而减小,并且边缘区域测点的相关性高于中间区域测点;测点风压的相干系数随着测点距离的增大而减小,且顺风向高于横风向。A measurement test of wind pressure distributions on the model of Guangzhou International Convention ＆ Exhibition Center was conducted in a boundary layer wind tunnel. The mean and fluctuating wind loads in 36 wind directions were obtained from the wind pressure measurements. Then, the power spectral densities, correlation coefficients and coherence functions of the wind loads were analyzed in detail. The influence of the wind field on the frequency domain characteristics of the fluctuating wind pressures was discussed. It was indicated that the power spectral densities of the fluctuating wind load have the characteristics of vortex shedding and Strouhal numer is about 0. 295; the correlation coefficients of across-wind loads are stronger than those of along-wind loads, all of them decrease with increase in the distance between the measured points, the correlation coefficients between the edge area points are stronger than those between the middle area ones; the coherence coefficients decrease with increase in the distance between the measured points, the coherence coefficients of along-wind loads are greater than those of across - wind loads.

关 键 词：大跨屋盖 风洞试验 功率谱 相关系数 相干函数 

分 类 号：TU973.32[建筑科学—结构工程]