Reliability-based service life assessment of corroded reinforced concrete bridge piers under seismic loading

Abstract This paper establishes a novel time-dependent structural reliability analysis framework for assessing corroded reinforced concrete (RC) piers, bridging the gap between probabilistic performance-based earthquake engineering and practical infrastructure management. The primary contribution is a holistic reliability model that uses the reliability index ( $$\beta$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>β</mml:mi> </mml:math> ) to evaluate competing failure criteria of excessive maximum drift (seismic performance) and residual drift (post-earthquake functionality). Through Monte Carlo simulations integrated with a validated nonlinear finite element model, the study quantifies seismic performance evolution over a 75-year lifespan under two seismic hazard levels. Key findings reveal a critical transition where residual drift supplants maximum drift as the governing failure criterion as corrosion progresses. Crucially, this work introduces a new prognostic framework that defines lost service life (LSL) due to corrosion and recovered service life (RSL) after maintenance actions, linked by an effectiveness coefficient. This framework translates reliability metrics into actionable RSL charts that quantify the life-cycle extension benefits of corrective maintenance. The results provide engineers with a powerful tool to shift from time-based to condition-based management, enabling data-driven decisions on repair strategies and lifecycle planning.