Experimental Investigations on Reinforced Concrete Gable Beams Strengthened with CFRP Sheets

Authors

  • Waleed Hassan Neama

    Department of Civil Engineering, Faculty of Engineering, University of Babylon, Al-Hillah 51002, Iraq
  • Hussein Talab Nhabih

    Department of Civil Engineering, Faculty of Engineering, University of Babylon, Al-Hillah 51002, Iraq

DOI:

https://doi.org/10.30564/jbms.v8i3.13543
Received: 22 May 2026 | Revised: 12 June 2026 | Accepted: 9 July 2026 | Published Online: 11 August 2026

Abstract

This study presents an experimental investigation on the structural performance of reinforced concrete (RC) gable beams strengthened with carbon fiber reinforced polymer (CFRP) sheets. A total of six RC gable beams were cast and tested under static loading applied at mid-span. One specimen served as a solid control beam, while two unstrengthened specimens incorporated eight circular or trapezoidal openings to reduce self-weight. The remaining three specimens featured identical geometries but were strengthened using CFRP sheets to enhance their bending and shear resistance. Evaluated parameters included load-deflection curves, ultimate load capacities, cracking patterns, failure modes, and structural strains. This research addresses a critical gap regarding the structural behavior and CFRP strengthening of perforated RC gable beams. Results demonstrated that incorporating openings successfully decreased beam self-weight by 14%, though inducing a minor 6.25% reduction in ultimate capacity. However, CFRP configurations significantly improved the load-carrying capacity by approximately 35% and substantially delayed crack propagation. Specifically, CFRP sheets delayed the first crack appearance, increasing its associated load by up to 82.35% when comparing the gable beam strengthening with CFRP sheets (GBS) specimen with the control gable beam (GB) specimen. Furthermore, the strengthening technique efficiently minimized concrete and steel strains across all specimens, reducing maximum concrete strain by 33.3%. Ultimately, the findings confirm that CFRP strengthening is highly efficient in eliminating the adverse structural effects of weight-reducing openings, ensuring structural integrity.

Keywords:

Reinforced Concrete Gable Beams; Variable Cross-Sections; Non-Prismatic Beams; Multiple Openings in Web; Strengthened with CFRP Sheets; Static Load

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How to Cite

Neama, W. H., & Nhabih, H. T. (2026). Experimental Investigations on Reinforced Concrete Gable Beams Strengthened with CFRP Sheets. Journal of Building Material Science, 8(3), 84–104. https://doi.org/10.30564/jbms.v8i3.13543

Issue

Vol. 8, Iss. 3 (September 2026): In Progress

Article Type

Article

License

Copyright © 2026 Waleed Hassan Neama, Hussein Talab Nhabih

Creative Commons License

This is an open access article under the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) License.

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