Damage detection of an innovative composite slab-girder pedestrian bridge using vibration characteristics

Abstract

This paper aims to detect and locate damage in an innovative slab-on-girder pedestrian bridge model using the vibration characteristics determined from a combined experimental–numerical procedure. The innovative slab-girder pedestrian bridge model has a bi-layer composite deck with Glass Fiber Reinforced Polymer as the bottom layer and laminated glass as the top layer to exploit the desirable properties of these two materials. Modal data from experimental tests and numerical analyses of the bridge model under single and multiple damage cases together with the modal flexibility method are used to detect and locate damage in the bridge. Results show that the peaks of the model flexibility plots correctly locate the damage and that their values provide a good indication of damage severity, which depend on the number of damages, damaged member and location of damage. Results show that the early vibration modes of this bridge model are dominant in torsion, different to flexure dominant modes in traditional slab-girder bridges. Nevertheless, the combined experimental-numerical procedure is found to be effective for assessing both single and multiple damages in the innovative bridge model. The adopted procedure will be applicable to similar real bridge structures in future investigations and will contribute to their safety.

Keywords:

• Damage detection
• laminated glass
• laminated glass fibre reinforced polymer
• modal flexibility change
• mode shape
• natural frequency
• slab-girder pedestrian bridge

Acknowledgements

The authors would like to express their sincere gratitude to the Queensland University of Technology for providing financial support and software facility to the first author during this research.

Data availability

The processed data required to reproduce these findings cannot be shared at this time due to legal reasons.

Disclosure statement

No potential conflict of interest was reported by the authors.

Table 6. Mode shapes and natural frequencies of damaged slab-girder bridge specimens in damage scenario 5.

Table 7. Mode shapes and natural frequencies of damaged slab-girder bridge specimens in damage scenario 6.