Composite Columns Reinforced with Rebars and Embedded I-Sections Made of Steel or GFRP: An Experimental Approach
Received: 14 May 2025 | Revised: 28 June 2025 and 10 July 2025 | Accepted: 11 July 2025 | Online: 6 October 2025
Corresponding author: Wed Hussein Habeeb
Abstract
This study experimentally investigates the structural performance of reinforced concrete columns incorporating steel and/or Glass Fiber Reinforced Polymer (GFRP) bars and I-sections under concentric loading. Six square columns (170 mm × 170 mm cross-section and 1500 mm height) with a compressive strength of 30.25 MPa were tested. Three reinforcement schemes were used: hybrid (GFRP I-sections with steel bars and vice versa), homogeneous (GFRP or steel I-sections with corresponding bars), and reference (bars only). A novel reinforcement technique employed four longitudinal I-sections with bars. The results indicate that the columns with I-sections outperformed the reference ones, with steel I-sections showing the highest capacity. The steel reference column exhibited 10.18% higher strength than its GFRP counterpart; the large steel I-section columns outperformed the GFRP ones by 57%, and the small steel I-section columns by 38%. This study highlights the potential of GFRP as a corrosion-resistant alternative in structural applications.
Keywords:
Glass Fiber-Reinforced Polymer (GFRP), composite column, GFRP I-sections, steel I-sections, concentric loadDownloads
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