AbstractThe aim of this study is to investigate the effect of corrosion on the hysteretic behavior of Q235 steel. To this end, the surface features of Q235 steel specimens subjected to different corrosion durations are determined using a reverse reconstruction method based on the experimental data of corrosion pit configuration. The buckling and hysteretic behaviors of these specimens are analyzed using a numerical simulation method that considers corrosion surface characteristics. The results show that the buckling of corroded specimens occurs at the weak parts of plates with large corrosion pits under cyclic loading. The surface characteristics have a significant influence on the buckling stress of corroded steel, which results in stress mutation at corrosion pits and a change in load gradient. In addition, an increase in the surface roughness and width-to-thickness ratio due to corrosion are the main reasons for the degradation of the buckling and hysteretic behavior of the corroded specimens. The ultimate load-carrying capacity and elastic stiffness decrease with increases in corrosion degree. The hysteretic energy of specimens decreases by nearly 33% as the average mass loss ratio increases by 19%. Finally, a nominal cyclic constitutive model of corroded steel is proposed, and the results essentially agree with the numerical simulation results.