Time-variant seismic resilience of reinforced concrete buildings subjected to spatiotemporal random deterioration

Corrosion-induced deterioration weakens the seismic capacity of buildings in coastal areas. This paper presents an investigation into the seismic resilience of RC frame structures experiencing spatiotemporal random deterioration. Two probabilistic distributions of corrosion were simulated using two modeling approaches: uniform and spatial corrosion assumptions. The incremental dynamic analysis (IDA) approach was used to obtain fragility curves for a 5-story RC frame designed according to Chinese codes. The impact of corrosion over a service life ranging from 0 to 50 years was assessed. The loss evaluation was subsequently conducted using the method proposed by Federal Emergency Management Agency (FEMA). The functionality curves and normalized resilience indices for different seismic hazard levels were estimated. The results indicate that the seismic probabilistic capacity and resilience of the 5-story RC frame studied here decrease as service time increases. The damage to structural members is more sensitive than that to nonstructural components. The total losses of the RC frame investigated in this study mainly result from nonstructural repair losses at first, then the collapse losses will become the main contributor to total loss as the seismic hazard level increases. Both uniform and spatial corrosion modeling approaches are valuable for representing the impact of corrosion on the restoration capabilities of RC frames.