Reliability of deteriorating RC slab bridges

Reinforced concrete (RC) bridges deteriorate with time. This results in reduction of their resistance, and, consequently, of their reliability. Corrosion of embedded reinforcing steel is one of the main causes of deterioration. The paper presents a method for reliability assessment of RC slab bridges with corroded reinforcement. The method includes a traffic load model, a corrosion model, and a nonlinear finite element structural model. Two types of corrosion-general corrosion, including spalling and debond between concrete and the corroded reinforcement, and localized corrosion - are considered. Reliability is estimated in terms of the reliability index using the first-order reliability method, Uncertainties associated with material properties, geometry, loads, and corrosion parameters are taken into account. A sensitivity analysis of a simple span bridge is carried out to examine the influence of these uncertainties on the bridge reliability. Reliability assessment of a deteriorated three-span continuous bridge illustrates the application of the method.