锥形涡及其诱导下的马鞍屋盖表面风荷载  

Conical vortex and its induced wind load on a saddle roof

作　　者：董欣[1] 叶继红[1] 

机构地区：[1]东南大学混凝土结构及预应力混凝土结构教育部重点实验室,南京210096

出　　处：《振动与冲击》2010年第10期61-70,共10页Journal of Vibration and Shock

基　　金：国家自然科学基金(50678036);江苏省土木工程研究生科技创新基金

摘　　要：通过刚性模型风洞测压试验,对锥形涡及其诱导下的菱形马鞍屋盖表面风荷载进行了系统研究:⒈分析了锥形涡诱导下的屋盖表面平均、脉动风压分布特点;通过脉动风压谱,着重分析了马鞍迎风前缘(易损区域)的平均、脉动风压分布机理。⒉通过风压信息确定了锥形涡的特征参数(涡核位置、作用范围),给出了定量结果;分析了锥形涡涡轴的左右摇摆运动,分别从定性和定量方面建立了锥形涡涡轴的运动与屋面吸力脉动之间的关系。⒊用测点风压时程的三、四阶矩对风压的非高斯特性进行描述,给出划分高斯、非高斯区的标准,并在此基础上对马鞍屋盖表面进行了分区;分析了锥形涡作用下屋盖表面风压非高斯特性的产生机理。Conical vortex and its induced wind load on a saddle roof were investigated with wind tunnel test.The mean and fluctuating pressure distribution associated with the conical vortex on the saddle roof were presented and discussed,with emphasis on the mechanism of wind pressure characteristics along the leading edge.Some feature parameters of the conical vortex,such as,the axis of the conical vortex and the coverage area,were identified through contour maps of the roof surface wind pressure coefficient.The sway of the axis of the conical vortex was analyzed,on the basis of which the qualitative and quantitative relations between the conical vortex movement and the suction fluctuation on the roof surface were established respectively.Based on the third and fourth order statistical moment of the wind pressure,non-Gaussian region on the roof surface was located.The mechanism of non-Gaussian feature related with the conical vortex was also clarified.

关 键 词：马鞍屋盖 风压分布机理 锥形涡 非高斯特性 90°风向 

分 类 号：TU312[建筑科学—结构工程]