Simplified expressions for the vibration serviceability of beam-like footbridges

Abstract

Simplified expressions presented in the British code BS 5400 and Eurocode 5 for the vibration serviceability of beam-like footbridges in the vertical direction due to pedestrian load were analysed. Adjustments made in such expressions improved their accuracy. In addition, two proposed expressions were presented. One of them followed the line of thought of the British code and was based on the use of a table and chart, which is simple but limited to predefined footbridge configurations. The other expression was not restricted to predefined configurations nor to predefined values for the speed or weight of the crossing pedestrian and damping of the structure. Numerical simulations and results from measurements showed that the proposed expressions generally improved the estimate of peak accelerations and also presented better performance than the code guidelines, particularly for the frequency range of the second harmonic of the pedestrian load.