Framework for lifecycle resilience assessment of earthquake-damaged coastal RC structures considering non-uniform corrosion

Abstract

Reinforced concrete (RC) structures in seismic coastal areas often suffer from the coupled effects of corrosion and earthquakes due to prolonged exposure to harsh environmental conditions. Previous research on the seismic performance of buildings primarily focused on uniform corrosion(UC), disregarding the impact of varying concentrations of chloride-ions on corrosion rate. This discrepancy will overestimate the seismic performance of building structures. The framework proposed in this study aims to evaluate the resilience of RC structures to non-uniform story corrosion(NUSC). The framework encompasses an innovative functional recovery function and considers the influence of chloride-ions concentration on the corrosion rate, time-varying initial functional function, and degradation model for corroded reinforced concrete. NUSC model is established within the proposed framework via OpenSees software. The proposed framework integrates the seismic hazard, fragility, resilience, and recovery models. A nonlinear time history analysis method is employed to simulate the structural response to the seismic action. The findings demonstrate that NUSC leads to a reduction in seismic resilience by 7.3% and 10% compared to UC when considering service times of 35 and 55 years, respectively. This indicates an escalation in seismic risk as well as a decline in structural seismic capacity.