Seismic Vulnerability of RC Buildings under the Effect of Aging

The present study aims at the assessment of the seismic vulnerability of reinforced concrete (RC) buildings considering performance degradation over time due to aging effects. Chloride induced corrosion is taken into account based on probabilistic modeling of corrosion initiation time and corrosion rate. Two-dimensional incremental dynamic analysis (IDA) is performed to assess the seismic performance of the initial uncorroded (t=0 years) and corroded (t= 25, 50, 75 years) RC fixed base frame structures designed based on different seismic code levels. The time-dependent fragility functions are derived at the various time periods in terms of spectral acceleration corresponding to the fundamental mode of the structure Sa(T1,5%) for the immediate occupancy (IO) and collapse prevention (CP) limit states. Results show an overall increase in seismic vulnerability over time due to corrosion indicating the significant effect of deterioration due to aging effects on structural behavior.