Effect of the correlation of steel corrosion in the transverse direction between tensile rebars on the structural performance of RC beams

Reinforcement corrosion is highly nonuniform and spatially distributed in reinforced concrete (RC) structures. Since RC members are reinforced with multiple rebars, corrosion of one rebar might affect another rebar in the transverse direction, thereby influencing the behavior of the structure. Hence, greater attention should be paid to studying the effects of the correlation of localized corrosion between adjacent rebars on the structural performance of RC members. In this paper, the effects of localized corrosion and the correlation of steel corrosion between tensile rebars on the structural performance of corroded RC beams were investigated through experiments and finite element (FE) analyses. The experimental results indicated that compared to the RC beams corroded over their entire length, the partially corroded RC beams with highly localized steel corrosion in the mid-span experienced large reductions in both loading capacity and ultimate deflection. Moreover, for beams with multiple rebars, the results showed that the beams with higher correlation coefficients of cross-sectional area loss between rebars had lower load and deflection capacities than the beams with lower correlation coefficients. The load–deflection responses of the beams with multiple rebars simulated by the 3D FE model were found to be in better agreement with the experimental results than those of the 2D FE model. Furthermore, a Monte Carlo simulation (MCS) was performed using a 3D FE model for two different cases: correlated and uncorrelated steel corrosion in the transverse direction of the RC beam. The results showed that a stronger correlation of steel cross-sectional area loss on different tensile rebars led to a larger variation in the load capacities of the corroded RC beams.