Footbridge edition:4 location:Wroclaw, Poland date:6-8 July 2011
Predicting the dynamic performance of civil engineering structures due to crowd induced loading is an increasingly critical aspect of the vibration serviceability design process. Due to the increasing strength of materials and the trend towards greater slenderness, modern pedestrian bridges are very often lively structures prone to human induced vibrations.
This paper presents the operational modal analysis of a footbridge in Eeklo (Belgium), by which accurate and reliable operational modal characteristics of the footbridge are obtained. These results are applied for the updating procedure of the numerical model (FE model) of the footbridge using the boundary conditions as updating parameters. An optimal correspondence is found between measured and calculated data, improving the accuracy of the model and increasing the reliability of the numerical predictions of the response of the bridge to pedestrian loading.
The vibration serviceability check according to the current codes of practice is performed for both the initial versus the updated model of the footbridge. In some cases this results into a different evaluation (comfort class), indicating the importance of a reliable estimation of the dynamic behaviour of the footbridge at design stage.