摘要
将人群步行荷载视为联合平稳随机过程,由行人之间的相干函数与已有单人步行荷载自功率谱模型,提出高、低两种密度下考虑行人之间相干性的互功率谱模型。引入医学领域的三维动作捕捉设备,解决人群步行试验中多人同步、时空变化的测试技术难题。通过对有约束状态下不同人群密度状况中试验数据的分析,分别确定两种密度下人群的步行频率分布和时间差参数、相干函数取值。利用建立的互功率谱模型,结合随机振动理论,在行人位置固定的假定下计算结构检测点的加速度均方根。通过人行桥人群步行试验结果和荷载模型理论预测结果的对比,验证该模型的实用性,为人群步行作用下结构的响应分析和舒适度评估提供新的频域方法。
By assuming that crowd walking load is a joint stationary stochastic process, a cross-spectral model for the low and high pedestrian densities in restricted traffic is proposed based on the coherence function and auto power-spectral density of individual walking load.The 3-D motion capture technology popularly used in medical science is introduced, to resolve the existing problems in crowd walking load experiment—incapable of recording the actions of all the pedestrians at the same time and the movements of pedestrians during walking.Based on the statistical analysis of tests, the distributions of walking frequency, time lag, and coherence function under different pedestrian densities are determined, respectively.Furthermore, the methodology of calculating structural acceleration response in terms of root mean square at the check point of the structure is established based on the cross-spectral model and the stochastic vibration theory.Under the assumption that the locations of pedestrians on the structure are fixed, the proposed model is verified by a comparison between the crowd walking experiment on a footbridge and the corresponding theoretical prediction using the developed methodology.Hence, the proposed model provides a new frequency domain method for the analysis of structural response and the assessment of vibration serviceability under crowd walking load.
作者
王晋平
熊杰程
陈隽
Wang Jinping;Xiong Jiecheng;Chen Jun(Tongji University,Shanghai 200092,China;Zhengzhou University,Zhengzhou 450001,China)
出处
《土木工程学报》
EI
CSCD
北大核心
2020年第7期12-20,共9页
China Civil Engineering Journal
基金
国家自然科学基金(51778465,U1711264)
协同创新中心项目(ZYJKFW201811009)。
关键词
人群步行荷载
人致荷载
振动舒适度
人致振动
人行桥
crowd walking load
human-induced load
vibration serviceability
human-induced vibration
footbridges
