长悬挑结构楼盖人致振动舒适度分析

Analysis on vibration comfort of long cantilevered structure floor

以天津某项目长悬挑结构楼盖为对象,通过建立其整体有限元分析模型,对长悬挑结构楼盖的自振特性以及在不同人行荷载激励下的振动响应进行了深入分析。分析结果表明,长悬挑结构楼盖的悬挑长度大,竖向刚度较小,前两阶竖向自振频率均小于3Hz;低频竖向振动处于人群荷载激励频率范围内,楼盖振动峰值加速度不满足规范限值要求,需要进行减振设计;布置调谐质量阻尼器后,长悬挑结构楼盖在人群荷载激励下的竖向加速度响应显著减小,减振率达到72.8%,减振后楼盖舒适度可以满足规范要求。

Taking a long cantilever structure floor in Tianjin as the object, the natural vibration characteristics of the long cantilever structure floor and its vibration response under different pedestrian loads are deeply analyzed by establishing its whole finite element analysis model.The analysis results show that the cantilever length of the long cantilever structure floor is large, the vertical stiffness is small, and the vertical natural vibration frequencies of the first two orders are both less than 3 Hz. The low-frequency vertical vibration is within the frequency range of the crowd load excitation, and the vibration peak acceleration of the floor can not meet the specification limit requirements, and vibration damping design is required. After arranging the tuned mass dampers, the vertical acceleration response of the long cantilevered structure floor under the crowd load excitation is significantly reduced, and the vibration reduction rate reaches 72.8%, and the comfort of the floor can meet the requirements of the specification after reducing vibration.