Existing walking models used for vibration serviceability assessment of pedestrian structures are typically based on measurements of single footfalls replicated at precise intervals. This assumed 'perfect periodicity' allows walking forces to be modelled as Fourier series based on the walking pace and its integer multiples. This paper examines the imperfection of real continuous walking forces and demonstrates via simulations significant differences from 'equivalent' perfectly periodic loading which tends to overestimate response due to higher harmonics. The random character of walking naturally leads to a stochastic approach to loading in the frequency domain which can be used for single pedestrians as well as crowd loading. The development of this model coincided with an exercise in assessing and mitigating serviceability problems in a long span footbridge and results from a crowd loading study to test for lateral dynamic instability provided some data for calibrating the model.
|Title of host publication||Proceedings of the 2004 International Conference on Noise and Vibration Engineering, ISMA|
|Number of pages||15|
|Publication status||Published - 1 Jan 2004|
Brownjohn, J. M. W., Pavic, A., & Omenzetter, P. (2004). Modeling and measuring dynamic crowd loading on a long span footbridge. In Proceedings of the 2004 International Conference on Noise and Vibration Engineering, ISMA (pp. 751-765) https://doi.org/10.13140/RG.2.1.1828.7849