Time-dependent Residual Flexural Strength of Corrosion-damaged Reinforced Concrete Beams Using Strength Degradation Models

As part of a research on the reuse of reinforced concrete (RC) members, a numerical study was conducted to evaluate the residual flexural strength of RC beams deteriorated by corrosion. To predict the residual flexural strength, a fiber analysis program was constructed based on strain compatibility using MATLAB. In the analysis, the reduction of effective rebar areas, degradation of rebar mechanical properties, degradation of bond strength between rebars and concrete, and degradation of concrete strength were considered. A total of 19 strength degradation models were generated through a combination of material models, and the predictions were compared with existing 85 test data for verification. The comparisons showed that the strength degradation models provided conservative estimates of the residual flexural strength. Furthermore, the accuracy of prediction was improved when the reduction of effective rebar areas, degradation of rebar mechanical properties, degradation of bond strength between rebars and concrete, and degradation of concrete strength were considered together.