Georgia Institute of Technology College of Sciences

In this talk, I will discuss recent advances and challenges in modelling complex dynamics of pedestrian-bridge interactions,  These challenges include a proper understanding of the biomechanics of walking on a moving structure and of the psychology of walking in crowds. I will explain the fundamental mechanism behind pedestrian-induced lateral instability of bridges due to some positive feedback from uncorrelated walkers whose foot forces do not cancel each other but create a bias. I will also present the results of our past and ongoing work that reveal the role of foot placement strategies and social force dynamics in initiating bridge instabilities. In particular, I will show that  (i)  paradoxically, depending on the human balance law (and the frequency of bridge motion), larger crowds can stabilize  bridge motions and (ii)  crowd heterogeneity can promote large vibrations of bridges.

Recording link:  https://bluejeans.com/s/h0TpdyBRatJ