Journal of innovative engineering and natural science (Online), cilt.6, sa.1, ss.275-294, 2026 (TRDizin)
Temperature causes many physical and chemical changes and has a negative impact on reinforced concrete (RC) structures. Long-term exposure to high temperatures reduces the strength and durability of RC elements and alters their seismic behavior. This study investigates the post-fire response of an RC column exposed to 600, 800, and 1000 °C following the ISO 834 standard fire curve. After natural cooling, the column behavior under cyclic lateral loading was analyzed. A finite element model was developed in ABAQUS to perform thermal analyses, followed by cyclic structural analyses. The effects of high temperature were evaluated in terms of changes in lateral load-carrying capacity and stiffness under different axial load levels. The results show that increasing temperature leads to a continuous reduction in both lateral load-carrying capacity and stiffness. At 1000 °C, these reductions reach approximately 53% and 85%, respectively. Based on these findings, RC columns exposed to temperatures of 600 °C and above 180 minutes should not be reused without strengthening. This study provides practical support for the post-fire evaluation of reinforced concrete structural elements.