Encased Pultruded GFRP Beams with Shear Connectors: A Review

Authors

  • Abbas A. Allawi Department of Civil Engineering, University of Baghdad, 17001, Baghdad, Iraq https://orcid.org/0000-0002-7792-8937
  • Teghreed H. Ibrahim Department of Civil Engineering, University of Baghdad, 17001, Baghdad, Iraq https://orcid.org/0000-0002-6524-8248
  • Enas M. Mahmood Department of Civil Engineering, University of Baghdad, 17001, Baghdad, Iraq
  • Tiba Hani Saadi Department of Civil Engineering, University of Baghdad, 17001, Baghdad, Iraq
  • Mohammed Riyadh Khalaf Department of Civil Engineering, University of Baghdad, 17001, Baghdad, Iraq
  • Hussein K. Mohammed Iraqi Ministry of Higher Education and Scientific Research, Iraq
Volume: 15 | Issue: 5 | Pages: 27551-27556 | October 2025 | https://doi.org/10.48084/etasr.12787

Received: 17 June 2025 | Revised: 3 July 2025 and 17 July 2025 | Accepted: 23 July 2025 | Online: 6 October 2025


Corresponding author: Abbas A. Allawi

Abstract

This study examines the structural performance of concrete-encased pultruded Glass Fiber Reinforced Polymer (GFRP) I-sections with shear connections. It specifically focuses on how different parameters affect the latter’s ductility, flexural strength, and load-carrying capacity. The key variables studied include various shear connector types, spacing, and geometries, as well as the compressive strength of concrete and the properties of GFRP. The finite element modeling and experimental validation show that the shear connectors significantly improve the ductility, ultimate capacity, and load transmission efficiency. The present review emphasizes that the shear connectors greatly enhance the structural performance when they are properly used. The long-term durability and failure modes must also be considered. For instance, having reduced the connector spacing from 375 mm to 100 mm increased the ultimate load by up to 34.5% in some cases, while having increased the concrete compressive strength from 30 MPa to 53.8 MPa led to a notable improvement in the flexural stiffness.

Keywords:

pultruded GFRP profile, encased beam, shear connectors

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[1]
A. A. Allawi, T. H. Ibrahim, E. M. Mahmood, T. H. Saadi, M. R. Khalaf, and H. K. Mohammed, “Encased Pultruded GFRP Beams with Shear Connectors: A Review”, Eng. Technol. Appl. Sci. Res., vol. 15, no. 5, pp. 27551–27556, Oct. 2025.

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Copyright (c) 2025 Abbas A. Allawi, Teghreed H. Ibrahim, Enas M. Mahmood, Tiba Hani Saadi, Mohammed Riyadh Khalaf, Hussein K. Mohammed

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