Seismic Performance Assessment of Corroded Reinforced Concrete Short Columns

Abstract

This paper presents an experimental study carried out on eight full-scale uncorroded and corroded reinforced concrete short columns subjected to the simulated seismic loading to investigate effects of corrosion on the seismic performance of short columns that failed in shear. The key variables are the corrosion level of reinforcement and the applied axial force ratio. The seismic behavior of test specimens was evaluated in terms of crack pattern, hysteretic response, shear strength, displacement ductility, drift capacity, and energy dissipation capacity. The experimental results highlighted that the corroded columns suffered a significant degradation of shear strength and deformation capacity as compared with uncorroded columns, especially when they are highly corroded and under high axial load ratio. Methods were proposed to estimate the shear strength of corroded short columns that failed in shear that consider the contribution reductions to the shear strength of transverse reinforcement and concrete due to corrosion. Among these methods, the shear strength of corroded RC short columns estimated based on both the average corrosion mass loss and average residual cross-sectional area was not conservative as compared with the test results. The shear strength of corroded short columns estimated using the minimum residual cross-sectional area of transverse reinforcement, however, showed good and reliable agreement with the test results in this study.