Experimental investigation on seismic performance of corroded reinforced concrete moment-resisting frames

For reinforced concrete (RC) structures located in seismic zones, reinforcement corrosion over time may have adverse effects on their seismic performance. Therefore, it is necessary to evaluate the effect of reinforcement corrosion on the seismic behavior of RC structures. In this study, an experimental study on corroded RC moment-resisting frames was carried out to investigate the effect of longitudinal reinforcement corrosion on the seismic behavior of RC frames. Six frame specimens, including five corroded frames and one frame without corrosion, were tested under quasi-static cyclic loading. The corrosion ratio of longitudinal reinforcement and the axial compression ratio were the main variable parameters. It was found that with the increase of corrosion ratio, the lateral load carrying capacity as well as the deformation capacity of RC frames decreased roughly linearly, and the energy dissipation capacity reduced approximately exponentially. For corroded frames with low axial compressive load level, the lateral strength and energy dissipation capacity were enhanced with the increase of the axial compression ratio, and the effect of axial compression ratio on the deformation capacity was insignificant. For frames with larger corrosion ratio or higher axial compression ratio, damages at beam ends developed more significantly during the loading process. In comparison with the beam, the damage evolution of columns was less affected by the corrosion ratio and axial compression ratio.