The Vibration Characteristics Of Concourse Hall Structure Of Large-scale Railway Passenger Station Under Vibration From Human Walking

ABSTRACT: With the rapid development of China’s high-speed railway in recent years, many large railway stations are constructed. Meanwhile, along with the widespreas utilization of new structural-design technology, new high-strength light materials and new construction methods in modern large railway stations, the spacing span becomes much longer, and the station structures become more light and flexible, which make the natural frequency of the structures lower. Because of the low-frequency vibration excited by walk-load, and it is close to the fundamental frequency of the station building structure, therefore, leading to the waiting passengers uncomfortable.In this thesis, the mechanical principle of the human walking, the relationship of walking speed and step frequency of human and the relationship of the speed and density of crowd are introduced. Then, the various single continual walking load curves and crowd walking load modals are compared, and at last, single continual walking load curve is expressed by Fourier series, and the certain random crowd load modal is used as the modal of crowd load of this thesis.Besides, the evaluation methods of the vibration serviceability in terms of the vibration amplitude, peaking acceleration and vibration level, etc. are introduced. In addition, the range of application, calculation methods and their advantages and disadvantages are introduced, as well. At last, the root-mean-square(RMS) acceleration of ISO2631:1997is applied as the main evaluation method in this thesis.At last, a large railway station concourse hall large-span structure finite element model is established by the large finite element software MIDAS/GEN, and modal analysis is conducted. According to the analysis of mode shape specialty, the most unfavorable position of the slab is determined. Then according to the time-history analysis of concourse hall large-span structure finite element model under different human walking load modals, the vibration regularity is obtained, and theoratical references are provided for the reasonable human walking load modals selection of concourse hall large-span structure. Moreover, the vibration regularity of different damping ratio and slab thickness is obtained, and the theoratical references are provided for reasonable size of structural design.