Decision support and structural assessment of a corroding reinforced concrete bridge considering new information

Abstract

Periodic visual inspections are the primary assessment method to ensure structural safety of existing bridges in practice. The influence of the collected inspection data on the structural reliability and consequential mitigation actions is usually only considered qualitatively. Advanced methods are available for consistent decision-making based on structural reliability analysis informed by inspection data. To demonstrate the practical implementation of advanced methods, the concepts are applied in a case study. Corrosion initiation by chlorides and corrosion propagation are modelled and updated with measurement data using Bayesian networks, resulting in a distribution of reinforcement cross-section loss. This loss is incorporated into the shear failure limit state, on which basis the probability of failure is estimated. In this modelling chain, the information from the chloride measurements directly influences the reliability assessment. The framework is also applicable to other deterioration phenomena and inspection data. This work provides bridge owners with methods to rationalise maintenance activities and ensure safe bridges on a limited budget.