大跨度组合楼盖人致振动分析与实测研究

为探讨大跨度组合楼盖的人致振动性能,基于单人脚步荷载模型,结合影响人群行走效应的因素,如人群分布、行走频率等,提出了一种人群激励的随机模拟方法.通过多点输入和时程分析法研究了某大跨度组合楼盖的人致振动反应,设计、研制了多组调谐质量阻尼器,并对该组合楼盖多个振动模态进行综合控制;实测了该大跨度组合楼盖在主体结构完成、整体结构完成2个阶段的动力特性;测试了阻尼器安装前、后组合楼盖在多种人群激励下的竖向加速度反应.研究结果表明:人群激励的类型和行走路线对楼盖振动反应影响显著;大跨度组合楼盖具有典型的模态密集特性,其在多种人群荷载激励下的竖向加速度反应较大;安装多组调谐质量阻尼器后,楼盖的人致振动反应显著降低且均满足人体舒适度的要求. 

Human-Induced Vibration Analysis and Measurement of Long-Span Composite Floors

In order to investigate the human-induced vibration performance of large-span composite floors, crowd excitation was simulated by the random method based on a normal footfall force curve and other individual factors such as crowd distribution and step frequency. Human-induced vibration responses of a large-span composite floor were analyzed with the help of the multi-support excitation and the time history analysis method, and multiple tuned mass dampers with different parameters were designed to control the vibration responses of the large-span floor. The actual dynamic properties of the composite floor under two distinct construction phases were tested, and vertical vibration responses of the composite floor with and without multiple tuned mass dampers under different crowd-induced excitations were measured. The research results show that the types and walking routes of human-induced excitations have significant effects on the floor responses and the large-span composite floor has very closely-spaced modes of vibration. The vertical acceleration responses induced by crowd excitation are relatively great under certain condition, and the human-induced responses of a structure with multiple tuned mass dampers decrease dramatically to meet the requirement of body serviceability.