Residual Flexural Capacity and Performance Assessment of Corroded Reinforced Concrete Beams

This paper presents an approach for evaluating concrete cracking growth and structural resistance deterioration due to reinforcement corrosion and for predicting future structural performance during the service life of the corroded concrete beams. The evolution of corrosion-induced concrete cracking is analytically predicted and then adopted for estimating the residual bond strength of the corroded steel rebar. The flexural capacity deterioration of a corroded concrete beam is accurately determined with consideration of rebar cross-section loss, yielding strength reduction and bond strength degradation caused by reinforcement corrosion. The concrete cracking growth and flexural capacity deterioration rates are chosen as random variables for modeling structural performance deterioration over time during the life cycle. The gamma process is then used for time-dependent stochastic deterioration modeling and the remaining life estimate of the corroded concrete beams. The results for the worked example show that the proposed approach can provide reliable predictions for concrete crack development and structural strength deterioration, and also give an effective method for lifetime performance assessment of the corroded concrete structures. (C) 2018 American Society of Civil Engineers.