Uncertainty quantification and propagation of crowd behaviour effects on pedestrian-induced vibrations of footbridges

The reliable prediction of pedestrian-induced vibration is essential for serviceability assessment and further mitigation design footbridges. response the footbridge governed by not only structure dynamic model but also crowd-induced load, which naturally involves randomness uncertainty. It consequently significant to appropriately characterize uncertainties during numerical modelling crowd behaviour effects on load. This work proposes a comprehensive approach quantify uncertainty from both behaviour, subsequently, propagate multiple sources input parameters footbridge. simulated using social force translated load combining with single pedestrian induced walking model. By decoupling continuous into several degrees freedom systems according relevant modes in evaluation, developed where structural responses are calculated. In this paper, all uncertain investigated together double-loop framework perform quantification propagation form probability-box (shortly termed as P-box). space peak finally obtained Monte Carlo sampling optimization outer loop inner loop, respectively. Feasibility performance overall demonstrated considering real scale footbridge, failure probability each comfort class regarding acceleration evaluated. Results show that, special attention should be paid epistemic aleatory assessments proposed may provide insights improve reliability future evaluations footbridges incorporating effects.