Probabilistic structural assessment of RC bridges under corrosion based on efficient simulation methods

The life-cycle assessment of structural reliability and seismic vulnerability of aging bridges is a key issue for optimal management of critical components of transportation systems. Predictive models of the structural performance should be able to integrate uncertainties associated with material properties and environmental stressors. In a life-cycle context, simulation-based methods relying on time-consuming non-linear structural analyses may require unfeasible computational efforts, especially when mechanical non-linearities are involved in structural response of deteriorating members. This paper presents a computational approach for lifetime structural reliability assessment of deteriorating Reinforced Concrete (RC) structures. The life-cycle numerical estimate of failure probability is evaluated over time based on suitable adaptation of Importance Sampling considering a Stationary Proposal distribution to efficiently select the sample structural models. The proposed methodology is investigated for seismic fragility assessment of a RC bridge pier under corrosion based on non-linear static pushover analysis.