中关村三小新校区体育馆屋盖人致振动控制研究

中关村三小新校区体育馆平面呈椭圆形,屋盖结构的最大跨度39.5m。体育馆屋盖结构具有自身阻尼小、跨度大以及刚度小等特点。基于建筑功能的需要,体育馆的屋盖兼做学校的操场使用。大跨度结构在人群荷载激励下容易产生较大的动力响应,使得屋盖结构的竖向振动加速度超过人体的耐受极限,给人造成不适甚至引起恐慌。采用SAP2000软件建立体育馆屋盖的整体模型,并对其进行模态分析,系统研究屋盖的竖向振动特点,根据结构自振特性,为减小振动不适感,在屋盖结构上布置了54个调谐质量阻尼器,参照中国规范和英国标准设定屋盖结构振动加速度限值。选取不同运动的荷载激励时程,通过多点输入计算屋盖结构的竖向加速度响应。理论分析和实测结果表明,该减振方案可以有效地减小振动,使屋盖满足舒适度要求。

Research on human-induced vibration control on gymnasium roof of NO.3 Zhongguancun Primary School

The gymnasium roof of NO.3 Zhongguancun Primary School has an elliptical plane,and the maximum span of the roof structure is 39.5m.The structure of the gymnasium roof has the characteristics of small damping,large span and low rigidity.Based on the needs of the building function,the roof of the gymnasium is also used as a playground for the school.The large-span structure is prone to generate a large dynamic response under the excitation of the crowd,so that the vertical vibration acceleration of the roof structure exceeds the tolerance limit of the human body,causing discomfort and even panic.The overall model of the gymnasium roof was built by SAP2000 software,and the modal analysis was carried out.The vertical vibration characteristics of the roof were systematically studied.According to the self-vibration characteristics of the structure,in order to reduce the vibration discomfort,54 tuned mass dampers(TMDs)were arranged on the roof structure.The vibration acceleration limit of the roof structure was set with reference to Chinese and British codes.The load excitation time history of different motions was selected,and the vertical acceleration response of the roof structure was calculated by multi-point input.Theoretical analysis and measured results show that the vibration reduction scheme can effectively reduce the vibration and make the roof meet the comfortableness requirements.