Abstract:
With the progress of ever-increasing span of footbridges and the application of modern light and high strength materials, as well as the pursuit of bridge aesthetic in urban areas, the fundamental frequency of modern flexible footbridges decreases significantly. Since the event of London Millennium Bridge which was closed due to excessive pedestrian-induced lateral vibration, considerable efforts have been devoted to pedestrian-induced vibration analysis, particularly the lateral vibration, and its mitigation for modern footbridges. In the present study, the fundamentals of pedestrian-induced vibration theory and dynamic design of footbridges are described. The emphasis is placed on three existing methods for analyzing the large-amplitude lateral vibration, namely the direct resonance method, the pedestrian-bridge interaction method and the parametric resonance method. Finally a curved cable-stayed footbridge is used as an example to demonstrate the dynamic design of footbridges.