Prediction of Nonlinear Flexural Behavior of Continuous RC Beams Pre-Damaged by Corrosion

Numerical simulation models capable of predicting the nonlinear flexural behavior of continuous reinforced concrete (RC) beams with corroded reinforcement were developed. Laboratory tests were conducted to validate predictions of the numerical models. A parametric study was carried out to examine the effect of varying the location and severity of corrosion on the nonlinear flexural behavior of continuous RC beams. The load capacity of continuous RC beams decreased linearly with an increase in the severity of corrosion, regardless of its location. The corrosion of reinforcement in the sagging region was, however, more detrimental to the load capacity than hogging corrosion. The rate of the strength reduction for the beam models with sagging corrosion was approximately 70% higher than that of the models with hogging corrosion. The beam models with sagging and hogging corrosion concurrently exhibited the poorest performance. The rate of the strength reduction of the beam models with corrosion in both sagging and hogging regions was approximately 2.7 times that of the models with hogging corrosion only. The moment redistribution ratio at the ultimate load for the beam models with sagging corrosion only ranged from 2-22%. The beam models with corrosion in the hogging region only exhibited the highest moment redistribution ratio of 22-50% at the ultimate load. The beam models with sagging and hogging corrosion simultaneously exhibited a constant moment redistribution ratio of 18% at the ultimate load.

Automated summary

Numerical simulation models were developed to predict the flexural behavior of corroded reinforced concrete beams, and laboratory tests were conducted to validate these models. The study found that the load capacity of the beams decreased linearly with the severity of corrosion, regardless of its location. Corrosion in the sagging region had a more detrimental effect on load capacity compared to hogging corrosion, with a strength reduction rate approximately 70% higher. Simultaneous corrosion in the sagging and hogging regions had the worst performance, with a strength reduction rate approximately 2.7 times higher than hogging corrosion only. Moment redistribution ratios varied depending on the location of corrosion, ranging from 2-22% for sagging corrosion only, and reaching a maximum of 22-50% for hogging corrosion only.