随机人群行走下大跨楼盖的动力特性参数及加速度响应的变化规律  

Dynamic characteristic parameters and acceleration response of large-span floor under random crowd walking

作　　者：操礼林[1] 王念康 CAO Lilin;WANG Niankang(Faculty of Civil Engineering and Mechanics,Jiangsu University,Zhenjiang,Jiangsu 212013,China)

机构地区：[1]江苏大学土木工程与力学学院,江苏镇江212013

出　　处：《江苏大学学报（自然科学版）》2024年第5期606-613,共8页Journal of Jiangsu University：Natural Science Edition

基　　金：国家自然科学基金资助项目(51878319,51408267)。

摘　　要：依据人在行走过程中变步长、变步频和变步速的关系,建立了一种随机人群步行荷载模型.基于薄板振动理论,推导了考虑人-结构相互作用的人群-大跨楼盖耦合动力方程,并通过编程计算,分析了随机人群作用下大跨楼盖动力特性参数与加速度响应的变化规律.结果表明:人群随机行走下,大跨楼盖瞬时频率先减小、后增大,瞬时阻尼比先增大、后减小;随着行走人数增多,大跨楼盖瞬时频率最小值显著降低,瞬时阻尼比最大值大幅增加,瞬时加速度和均方根加速度均呈先增后减的趋势;不同行走人数下,考虑与不考虑行人随机性时结构的加速度响应差异较大,其中瞬时加速度最大差异率可达到53.90%,均方根加速度最大差异率可达到61.57%.To accurately predict the vibration response of large-span floor under crowd walking,the random crowd load model was established according to the relationship among variable step size,variable step frequency and variable step speed during pedestrian walking.Based on the thin plate vibration theory,the crowd-large-span floor coupling dynamic equation considering human-structure interaction was deduced,and the variation rule of dynamic characteristic parameters and acceleration response of large-span floor under random crowd action was calculated and analyzed.The results show that under the random crowd walking,the instantaneous frequency of the large-span floor is decreased with latter increasing,and the instantaneous damping ratio is increased with latter decreasing.With the increasing of the number of people walking,the minimum instantaneous frequency of the structure is decreased significantly,and the maximum instantaneous damping ratio is increased significantly,while the instantaneous acceleration and root mean square acceleration of the large-span floor show the trend of increasing with latter decreasing.Under the different number of people walking,the acceleration response of the structure with and without pedestrian randomness is significantly different.The maximum difference rate of instantaneous acceleration can reach 53.90%,and the maximum difference rate of root mean square acceleration can reach 61.57%.

关 键 词：人致振动 大跨楼盖 随机人群 人-结构相互作用 振动分析 

分 类 号：TU311.3[建筑科学—结构工程]