大跨度平屋面结构的气动抗风措施及其机理分析  

Aerodynamic wind-resistance measures of long span cantilevered flat roof structures and their mechanism analysis

作　　者：傅继阳[1] 

机构地区：[1]暨南大学力学与土木工程系,广东广州510632

出　　处：《暨南大学学报（自然科学与医学版）》2007年第1期79-83,共5页Journal of Jinan University(Natural Science & Medicine Edition)

基　　金：国家自然科学基金项目(50608037);广东省科技计划项目(2006B37201011)

摘　　要：通过综合一些典型大跨度平屋面结构的风洞试验结果,分析了这种结构风敏感方向的风压分布特征及其产生机理.用频域相干分析法间接地证实了锥形涡的存在,并指出它是造成此类结构角区附近负压显著偏大的主要原因.针对此类结构的风压分布特征,提出了气动抗风措施.试验结果显示它可以干扰锥形涡的形成,大大削减风敏感部位的风荷载值,使平均局部体型系数降低约50%.Some wind tunnel experimental results for typical long span cantilevered flat roof structures are presented in this paper. The largest peak suction values are observed from pressure taps beneath conical ＂delta-wing type＂ comer vortices that occur for oblique winds, then the characteristics and causes of the local peak suctions are discussed in detail. Furthermore, it is verified that the peak suctions are highly correlated with the conical vortices by coherence functions of fluctuating pressures. Finally, according to the characteristics of wind loads on the roof, an aerodynamic solution to minimize the peak suctions by venting the leading edges and the comers of the roof is recommended. The experimental results show that the suggested strategy can effectively control the generation of the conical vortices and make a reduction of 50% in mean local shape factors at wind sensitive locations on the roof.

关 键 词：大跨屋盖 风荷载 相干函数 锥形涡 气动抗风措施 

分 类 号：TU312.1[建筑科学—结构工程] V211.74[航空宇航科学与技术—航空宇航推进理论与工程]