Analytical Model for Concrete Jacketed RC Columns with Precorrosion and Postcorrosion Damages Under Uniaxial Loading

The main objective of this study is to investigate the effect of precorrosion and postcorrosion damage on concrete jacketed RC columns under uniaxial loading and to develop a rational methodology for predicting the corresponding compressive strength. The predamage and postdamage involved an electrochemical process to accelerate the migration of chlorides from an external electrolyte into the tested columns and a wetting–drying cycle process with a controlled current to speed up the corrosion of the reinforcing steel bars in the tested columns. An uniaxial loading test was to determine the structural performance of the concrete jacketed columns with or without corrosion damage. The failure mode, load–displacement, and load–strain responses of test columns were recorded, and the related mechanisms were discussed. Then a model that is capable of evaluating peak load of unjacketed or jacketed RC columns with or without corrosion damage was developed. The analytical approach considered the effect of reinforcement corrosion on the effective load-bearing area of concrete and the confinement effect from the web reinforcement. The analytical results agreed well with the experimental results, indicating the reliability and effectiveness of developed models.