Cost-based recovery processes and seismic resilience of aging bridges

The life-cycle optimization of cost-effective post-earthquake recovery processes under target levels of seismic resilience is formulated for concrete bridges exposed to corrosion. The seismic capacity is assumed as time-variant functionality indicator and resilience is evaluated by considering the dependency on the time of occurrence of the seismic event. The life-cycle cost of the recovery process repair is formulated by taking both the direct cost of the repair interventions and the indirect economic loss due to the bridge outage into account. The proposed approach is applied to a four-span continuous bridge with box cross-section piers exposed to corrosion. The results show that the detrimental effects of structural deterioration may affect the cost-effectiveness of the recovery processes and lead over time to a significant increase of the recovery costs.