Probabilistic analysis of human-structure interaction in the vertical direction for pedestrian bridges

This paper deals with the quantification of the effects of human-structure interaction in the vertical direction for footbridges. Analyses are based on the study of a coupled system of the footbridge, modeled as a continuous dynamic system, and pedestrians, schematized as moving single-degree-of-freedom systems, characterized by random dynamic properties. The equivalent dynamic properties of the coupled system are estimated based on a state-space approach. Results of Monte Carlo simulations show that pedestrians can strongly modify the dynamic properties of the footbridge, especially regarding the damping ratio. A numerical application to some literature examples shows that the model is able to reproduce experimental findings on real footbridges.