Interval serviceability assessment of footbridges

This paper studies serviceability assessment of footbridges through a non-deterministic approach. The parameters defining pedestrian-induced loading and the structural dynamic properties are characterized through possible ranges of variation. Starting from analytical expressions for the spectral moments of the structural response, the improved interval analysis is applied together with an optimization strategy that allows us to obtain the bounds of the standard deviation of the footbridge acceleration and of the mean value and cumulative distribution function of its maximum value. Based on this approach, a possible interval of variation of the structural response is evaluated, rather than a single deterministic value. Thus, an interval level of comfort can be defined.