Capturing Spatiotemporal Progression of Corrosion to Estimate Life-Cycle Seismic Resilience of RC Bridges

Corrosion is a major threat to RC bridges for their lifelong safety and sustainability. This article investigates the spatiotemporal progression of corrosion degradation in piers of a RC bridge and estimates its impact on life-cycle seismic resilience of the bridge. Spatial randomness of corrosion and concrete parameters along the length and periphery of piers were generated through the spectral representation method. Generated random fields were integrated with the multiphysics phenomena of corrosion in the COMSOL Multiphysics platform for a realistic simulation of corrosion propagation on rebars in bridge piers. Obtained information was then inserted to the finite-element model of the bridge composed of all essential features to accurately capture this gradual degradation for seismic performance assessment of the bridge in a life-cycle context. In this performance simulation, the study considered both spatial and nonspatial corrosion strategies in the presence and absence of early-age surface cracks and estimated the variation in measured seismic resilience of the bridge for various corrosion strategies. Results depict significant overestimation of seismic resilience of the bridge along its life span if the spatial nature of corrosion is ignored, and thus highlights the importance of considering the same for seismic response analysis of aging bridges.