Shear Resistance of Beams Reinforced with GFRP Reinforcement

Abstract:

Fiber-reinforced polymers (FRP) have been used for decades in aerospace, sports, the automotive industry, and other sectors. In the construction field, they found their application in the early 1950s. Typically, they are used in structures as direct reinforcement in areas with aggressive or chemically demanding environments. This paper focuses on glass fiber-reinforced polymer (GFRP) stirrups combined with longitudinal GFRP reinforcement in elements. It explores the possibility of an alternative solution to traditional steel reinforcement in concrete structures. This application would be suitable, for example, on bridges exposed to an aggressive environment containing chlorides from de-icing salts, where stirrups are the first to corrode after the concrete cover is damaged by carbonation, due to their position closest to the surface.The article is primarily focused on the assessment of the shear resistance of a concrete element reinforced with GFRP shear reinforcement. It is relatively problematic to develop a calculation model that would correctly capture the effect of GFRP stirrups on shear resistance, as well as the decrease in the tensile strength of the stirrups at the bend location. The analysis in this paper deals with determining the predicted shear resistance of a concrete element reinforced purely with GFRP reinforcement and comparing these values with experimentally measured values from a selected experimental study. The article compares the measured results with the experiment, with the most accurate agreement achieved by the results according to EN 1992-1-1:2023 and ACI 440.11-22. The shear resistance calculated by the CNR-DT 203/2006 standard was higher, thereby significantly overestimating the capacity compared to the experimental results. The updated version, CNR-DT 203/R1/2025, provides relatively accurate results that can be considered acceptable for practical use. Conversely, the values calculated by the CSA S806-12 and AFGC standards are significantly lower, meaning they substantially underestimated the shear resistance of the beams.

• Periodical: Advances in Science and Technology (Volume 176)
• Pages: 83-88
• DOI: https://doi.org/10.4028/p-iKx8o0
• Online since: May 2026
• Authors: Dárius Bálint, Róbert Sonnenschein*
• Keywords: Design of GFRP for Shear, GFRP Stirrups, Shear Resistance

References

[1] Y.A. Al-Salloum, S. El-Gamal, T.H. Almusallam, S.H. Alsayed, M. Aqel, Effect of harsh environmental conditions on the tensile properties of GFRP bars, Compos. B Eng. 45 (1) (2013) 835–844.

DOI: 10.1016/j.compositesb.2012.05.004

[2] National Research Council. Guide for the Design and Construction of Concrete Structures Reinforced with Fiber-Reinforced Polymer Bars. CNR-DT 203/2006. Rome, Italy: CNR; 2007.

[3] ACI Committee 440. Building Code Requirements for Structural Concrete Reinforced with Glass Fiber-Reinforced Polymer (GFRP) Bars—Code and Commentary. ACI CODE-440.11-22. Farmington Hills, 48331 MI: ACI; 2023.

DOI: 10.14359/51738838

[4] Canadian Standards Association (CSA). Design and construction of building structures with fibre-reinforced polymers. CAN/CSA S806-12. Mississauga, ON, Canada: Canadian Standards Association (CSA); 2021.

DOI: 10.1201/9781003072089-52

[5] European Committee for Standardization. Eurocode 2 - Design of concrete structures - Part 1-1: General rules and rules for buildings, bridges and civil engineering structures. EN 1992-1-1:2023 E. Brussels, Belgium: CEN-CENELEC; 2023.

DOI: 10.3403/30430557

[6] AFGC. Recommendations for the use of FRP (Fibre Reinforced Polymer) rebars for reinforced concrete structures. AFGC; 2023.

[7] National Research Council. Guide for the Design and Construction of Concrete Structures Reinforced with Fiber-Reinforced Polymer Bars. CNR-DT 203/R1/2025. Rome, Italy: CNR; 2025.

[8] BYWALSKI, Czesław; DRZAZGA, Michał; KAŹMIEROWSKI, Maciej; KAMIŃSKI, Mieczysław. Shear Behavior of Concrete Beams Reinforced with a New Type of Glass Fiber Reinforced Polymer Reinforcement: Experimental Study. Materials. 2020, vol. 13, no. 5, 1159.

DOI: 10.3390/ma13051159