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Due to a trend in designing light and slender structures, many modern footbridges are prone to excessive vibrations. Severely vibrating footbridges can give rise to discomfort for the pedestrians. Therefore, during the last decades, pedestrian-induced vibrations of footbridges have become a subject of great interest. In this study, the performance of a coupled crowd-structure model, where the bridge is described using its first two modes of vibrations and each pedestrian is described as a moving mass-spring-damper system, in combination with a walking load, is evaluated. The model is used to estimate vertical deck accelerations of a real footbridge which is known to be susceptible to vibrations, and the results are then compared to measurements. The model performs satisfactory in the time domain, but poorly in the frequency domain, which is concluded to be mainly due to discrepancies in the simulated load compared to the measured load.

<p>Due to an increasing interest in recreational running, groups of jogging people becomes a more frequent load case on footbridges. The studies related to runners on footbridges are very limited and according to current design guidelines, running loads can be neglected. This study aims at investigating if the effect of running pedestrians on a footbridge is negligible. In order to do so, a case study comprising field tests and numerical simulations using three modelling approaches is performed. For a group of walking people, the footbridge experiences accelerations well below the limit given by the design guidelines, while for a single person running, the acceleration limit is exceeded. Therefore, the main conclusion is that, in certain cases, it is highly motivated to include runners as a required load case in the design phase of a pedestrian bridge, even though walking might not cause any problems. Furthermore, it is concluded that, for this particular bridge, two of the numerical models give desirable correspondence between simulations and measurements.</p>