Investigation of structural behavior of corroded RC columns

Due to the reinforcement corrosion that occurs in reinforced concrete elements, the targeted performance levels of the structures are negatively affected. The main negative effects of corrosion on reinforced concrete elements are the decrease in the area of the reinforcement, the volumetric expansion of the corrosion products and the cracking of the concrete, the decrease in the adherence force between the concrete and the reinforcement. In this context, the researches conducted to evaluate the structural performance of rusted reinforced concrete columns are still important. Within the scope of this thesis study, 5 reinforced concrete columns were tested in order to examine the effect of high levels of reinforcement corrosion on the structural behavior of reinforced concrete columns. One reinforced concrete column was not exposed to corrosion as a reference sample, and accelerated corrosion processes were applied to other specimens at different levels in the corrosion pool. After the rusting process, the width of primary cracks caused by corrosion on the specimens was measured with the help of a microscope and crack maps were created. With the obtained crack width values, empirical models predicting the corrosion rate from primary crack widths in the literature were verified. Reinforced concrete column specimens were tested under constant axial load by applying incremental reversible repetitive lateral load. After the loading tests, the samples were broken, the longitudinal reinforcements and winding fittings were removed and mechanically cleaned of corrosion residues. Final weights of the rebars were recorded with precision scales and the actual corrosion rates of the samples were calculated. In the light of all experimental data obtained, energy-based empirical models have been proposed to determine the seismic performance levels of reinforced concrete columns exposed to corrosion.