Behavior of Concrete Columns Using High-Performance Concrete Mixed with Steel Fibers in Prefabricated Steel Tubes as Reinforcement

Abstract

This study investigated the behavior of reinforced concrete columns using high-performance concrete (HPC) filled in prefabricated steel tubes to serve as reinforcement. The experimental setup involved HPC with a compressive strength of 1,515 kg/cm², filled into steel tubes with diameters of ¾, 1, and 1¼ inches, replacing the reinforcement in concrete columns sized 150x150x600 mm. The concrete used for casting the sample columns had a compressive strength of 257 kg/cm². The columns were tested for axial and eccentric loading at displacements of 20, 40, and 60 mm to determine the maximum compressive strength, bending moment, interaction diagrams, and failure patterns of the steel-reinforced concrete columns. The experimental results showed that the axial compressive strength of columns using HPC in steel tubes as reinforcement was higher than that of the control concrete columns. The compressive strength at various eccentricities showed a slight increase compared to the control columns. The comparison between experimental compressive strengths and bending moments with calculated values indicated a consistent trend. Furthermore, the failure patterns of the concrete columns revealed both compression and tension failures.

Keywords

• high-performance concrete
• prefabricated steel tubes
• steel fibers
• reinforced concrete columns