下击暴流作用下不同深宽比的高层建筑风荷载  

Wind loads of high-rise buildings with various aspect ratios in downburst wind

作　　者：方智远 李正良[1,2] 汪之松[1,2] Fang Zhiyuan;Li Zhengliang;Wang Zhisong(School of Civil Engineering,Chongqing University,Chongqing 400045,China;Key Laboratory of New Technology for Construction of Cities in Mountain Area of Ministry of Education,Chongqing University,Chongqing 400045,China)

机构地区：[1]重庆大学土木工程学院,重庆400045 [2]重庆大学山地城镇建设与新技术教育部重点实验室,重庆400045

出　　处：《东南大学学报（自然科学版）》2019年第3期488-494,共7页Journal of Southeast University：Natural Science Edition

基　　金：国家自然科学基金资助项目(51208537)

摘　　要：为研究下击暴流作用下高层建筑的风荷载特性,采用冲击射流装置对5种不同深宽比的高层建筑模型进行测压试验,分析了深宽比和径向距离对模型局部和整体风荷载的影响.结果表明:层阻力系数沿高度方向呈下大上小的分布特征,最大层阻力系数出现在0.25H(H为建筑高度)左右,层脉动升力系数沿高度变化较为平缓;随深宽比的增大,层平均阻力系数略有减小,层脉动升力系数显著增大,模型整体的平均阻力系数和顺风向弯矩系数略有减小,整体的脉动升力系数及横风向弯矩系数明显增大;随径向距离的增大,层平均阻力系数迅速减小,层脉动阻力系数和脉动升力系数先增大后减小,模型整体的平均阻力系数和弯矩系数迅速减小,整体的脉动阻力及升力系数先增大后减小.To study the wind load characteristics of high-rise buildings in downburst wind, an impinging jet device was used to carry out the pressure tests on 5 high-rise building models with different depth-to-width ratios. The influence of the aspect ratio and the radial distance on the local and overall wind loads was analyzed. The results show that the distribution characteristics of the layer drag coefficients along the height direction are larger in the lower part and smaller in the upper part of the building models. The maximum of the layer drag coefficients occurs at the height of about 0.25 H ( H is the height of the building), and the fluctuating lift coefficients of the layers change smoothly along the height. With the increase of the depth-to-width ratio, the average of the layer drag coefficients decreases slightly while the fluctuating layer lift coefficient increases significantly;as for the whole model, the mean drag coefficient and the along-wind bending moment coefficient decrease slightly, while the fluctuating lift coefficient and the cross-wind bending moment coefficient increase obviously. With the increase of the radial distance, the mean layer drag coefficient decreases rapidly;the fluctuating layer drag coefficient and the lift coefficient increase first and then decrease;as for the whole model, the mean drag coefficient and the bending moment coefficient decrease rapidly, while the fluctuating drag and the lift coefficient increase first and then decrease.

关 键 词：下击暴流 冲击射流 高层建筑 风荷载 

分 类 号：TU312.1[建筑科学—结构工程]