Influence of different degradation mechanisms on structural robustness: the case study of a reinforced concrete arch bridge

The robustness of a structural and geotechnical system is understood as the ability to prevent or reduce the consequences of a local (exceptional and/or extreme) event. The current work aims to address the issues related to the evaluation of robustness of structures with incorporated damage. A case study on an existing reinforced concrete arch bridge is investigated by evaluating its robustness considering the variation of both the state of cracking from concrete spalling and corrosion of the reinforcement bars. The damage variation related to these different issues is assessed both in terms of intensity and occurrence in the various structural elements of the bridge. Finally, the structural robustness index is estimated through push-down analysis to make an overall assessment of the bridge behaviour.