柱壳屋盖的等效静风荷载

根据弹性恢复力的模态展开式和计算响应的拟静力公式导出产生屋盖结构最大峰值响应的等效静风荷载。给出两种计算等效静风荷载的途径,一种表示为模态等效静风荷载的加权组合,另一种表示为背景分量与共振分量的加权组合。利用同步多点压力扫描技术对一个柱壳屋盖结构进行了风洞试验。采用完全二次型组合法(CQC法)和平方总和开方法(SRSS法)计算了不同风向角下竖向位移的峰值响应,说明了模态耦合的影响。将两种途径计算的柱壳屋盖等效静风荷载分布与平均风荷载分布作了比较,分析了相应的峰值响应与平均响应。分析结果表明:许多结点的等效静风荷载远大于平均风荷载,而且脉动风效应和共振效应也应引起重视。

Equivalent Static Wind Loads of Cylinder Roof

The equivalent static wind loads(ESWL) producing maximum peak responses of roof-structures were formulated based on the modal expansion of the resilience and the quasi-static equation for calculating responses.Two approaches to compute ESWL were presented,where one approach was expressed as a weighted combination of the modal equivalent static wind loads,and the other was expressed as a weighted combination of the background component and resonant component.Wind tunnel experiments of a cylinder roof were conducted by means of the synchronous multi-pressure scanning technique.The peak responses of the vertical displacement at different wind azimuths were calculated with the complete quadratic combination(CQC) method and the square root sum of square(SRSS) method,and the effects of modal coupling were checked.The distributions of the equivalent static wind loads on the cylinder roof obtained from two approaches above were compared with the mean wind loads,and the corresponding peak responses and mean responses were analyzed.The analysis results indicate that the equivalent static wind loads acting on many nodes are much greater than the mean wind loads,and the effects of fluctuating wind and resonance are deserving of attention.