ABSTRACT
Vibration-based structural health monitoring is an efficient technique for dynamic assessment of the structures. Based on the identified dynamic characteristics, the condition of a bridge can be assessed by means of structural identification through the finite element model updating procedure. The modal parameters are generally the indicators that reflect the changes of the global performance of the bridges. As the supplement, non-destructive evaluation methods can be employed to provide more detailed information about the local condition of the structure. In this study, operational modal analysis was performed on a butterfly-arch pedestrian bridge at Fuhzou Univesity, which was based on an innovative design concept, known as the stress-ribbon bridge. The uncertain model parameters of the structure were identified by updating the refined FE model in reference to the experimental modes. The ultrasonic instruments and rebound hammers were used to determine the debonding condition of the concrete-filled steel tubular sections of the main arches and the elastic modulus of the concrete slabs, respectively. Both of them play an important role to influence the dynamic behaviour of the bridge. The key structural parameters that were identified by the FE model updating procedure are compared to the nondestructive testing results. It’s found that the nondestructive testing methods provide important supplementary information to the SHM for condition assessment of the structure.
