Seismic Reliability Assessment of an Open-Spandrel Reinforced Concrete Arch Bridge

This work deals with the seismic reliability assessment of an existing double-span open spandrel RC arch bridge designed only for gravity loads, aiming to assess its seismic structural safety. In this context, the seismic reliability analysis is a powerful tool able to combine seismic hazard and structural fragility for computing the probability of failure of a specific damage state of interest. The present work applies this well-consolidated procedure to the specific case study of an open spandrel RC arch bridge located in North-eastern Italy, adopting as suitable engineering demand parameters for both the ductile and fragile failure mechanism of the columns between the RC arches and the RC beams grillage. Collapse seismic fragilities are computed for each structural element and, finally, the bridge seismic reliability is computed in a system reliability-based format.