Pedestrian-induced Vibration And Control Of Footbridges

Footbridge vibration induced by pedestrians is a tough issue that society is facing and must be mitigated.The modern footbridges are most slender structures,characterized by long spans,low weight materials and small damping ratio.Therefore,the vibrations are easy to be induced by pedestrian footsteps.This research was initialized for finding the solutions for these issues caused by the pedestrians,which impacts not only the pedestrian comfort but also structural integrity.The primary research work and conclusions of this paper include:1.The footbridge structure background was discussed and the issues discovered.The dynamic response factor for SDOF with and without tuned mass dampers is determined to see how the tuned mass dampers are effective in reducing the resonance in the structures.2.The numerical models for pedestrian bridge with and without tuned mass dampers were modelled into Abaqus software and the case carried out in this thesis was taken as Millennium Bridge.The dynamic loads induced by pedestrians were studied and implemented into the FE analytical models.3.The displacement and acceleration of footbridge without dampers subjected to crowds have been determined.It was clearly shown that with the absence of dampers,the high response should occur at any instance when large numbers of people are crossing on the bridge.4.The tuned mass dampers with suitable properties on the footbridge gave a considerable effect for reducing responses after properly inserted into the model.5.The responses before and after attaching tuned mass dampers were compared and later compared to those of the comfort criteria as recommended by guidelines.