Long-term vibration serviceability of a steel-plated stress ribbon footbridge

This paper describes the dynamic analysis and vibration serviceability assessment of an in-service steel-plated stress-ribbon footbridge sited in Valladolid (Spain). Because of ist slenderness and singularity, this footbridge is a typical lightweight structure sensitive to dynamic excitation produced by pedestrians. A continuous vibration monitoring system which measures the acceleration and the environmental factors has been installed. The data collected have been used to identify the dynamics of the structure and assess ist vibration serviceability under in-service pedestrian traffic. Firstly, peak-acceleration-based test for single-frequency excitations are undertaken. Secondly, standards ISO 2631 and ISO 10137, suitable for general human exposure evaluation to whole-body vibrations, are used to evaluate the long-term vibration serviceability since they take into account the duration of the vibration exposure as well as the frequency content of the excitation.