Using Full-Scale Observations on Footbridges to Estimate the Parameters Governing Human–Structure Interaction

The further development and improvement of prediction models for crowd-induced vibrations footbridges requires detailed information on representative operational loading data. In this paper, an inverse method is used to estimate the parameters that govern human–structure interaction from resulting structural response. interest concern dynamic characteristics a mass-spring-damper (MSD) system, applied describe mechanical between pedestrian structure. MSD model are estimated by minimizing discrepancy observed simulated power spectral density parameter estimation procedure assumes behavior empty structure, average weight, distribution step frequencies in crowd known. proposed approach verified using numerical simulations influence modeling errors investigated. results show as human body nature lightly (≲2%) strongly (≈30%) damped, respectively, response most sensitive small variations natural frequency model. results, furthermore, problem mostly related mean value modes’ modal mass. impact found decrease increases. Next, two real where walking induced high densities observed. (≈3.0 Hz) damping ratio (≈34%) obtained accordance with recent findings literature. These estimates are, however, first time ever, it believed, based full-scale observations involving densities.