An Analytical Study of Hybrid Reinforced Concrete Columns on Combined Bending

In recent decades, polymeric fibers have garnered heightened interest as a substitute for steel reinforcement due to their corrosion resistance, high tensile strength, and lightweight properties. Nevertheless, their linear elastic stress–strain response and absence of a plastic stage impede their application in compression members, particularly in RC columns and earthquake-resistant sections, as stipulated by design codes. In order to address these limitations, this study explores a hybrid reinforcement combining steel and polymer bars to balance strength, ductility, and durability. A finite element model was developed using ANSYS and validated against published experimental data, enabling the comparison of steel-, polymer-, and hybrid-reinforced concrete columns under combined bending with equal elastic moduli for steel and polymer bars. The findings indicated that polymer-reinforced columns exhibited a 16% higher load capacity compared to steel-reinforced columns, though steel columns demonstrated superior ductility. Hybrid columns exhibited approximately 9% greater load capacity than steel columns while demonstrating enhanced plasticity, suggesting that they provide an economical and durable alternative, particularly in environments prone to corrosion and moisture exposure. This research underscores the potential of hybrid reinforcement in achieving both structural efficiency and sustainability in concrete column design.