An Experimental Research Into the Bonding Strength of GFRP Bars in Concrete Under Elevated Temperatures

Authors

  • Ahmed Yahya Gaeeb University of Kirkuk
  • Muayad Mohammed Kassim University of Kirkuk

DOI:

https://doi.org/10.61132/ijmecie.v1i1.143

Keywords:

Bar Slippage, Bond Strength, Elevated Temperatures, GFRP Bars, Thermal Degradation.

Abstract

This study investigates the bond strength of Glass Fiber Reinforced Polymer (GFRP) bars in concrete at high temperatures. Twenty-four specimens were tested at 600°C to replicate fire conditions and analyze performance consequences in structural applications, with variables such as bar diameter and position within the concrete taken into account. The results show a considerable drop in binding strength, notably in edge-positioned bars with thinner covers, which is related to thermal degradation of the epoxy resin. The stress-slip relationship revealed significant increases in slippage, particularly for bigger diameter bars, as well as the vulnerability of GFRP bars to high temperatures. Failure modes shifted mostly to splitting following exposure, emphasizing the importance of design concerns in fire-prone structures. These findings improve our understanding of GFRP performance in harsh situations, influencing material selection for greater fire resilience.

 

References

Albu-Hassan, N., & Al-Thairy, H. (2020). Experimental and numerical investigation on the behavior of hybrid concrete beams reinforced with GFRP bars after exposure to elevated temperature. Structures, 24, 139–148. https://doi.org/10.1016/j.istruc.2020.06.011

Allah, S. J. S., Kassim, M. M., & Salman, G. A. (2024). The durability of concrete mortars with different mineral additives exposed to sulfate attack. Salud, Ciencia y Tecnología-Serie de Conferencias, 3, 851–851.

Aslani, F. (2019). Residual bond between concrete and reinforcing GFRP rebars at elevated temperatures. Proceedings of the Institution of Civil Engineers - Structures and Buildings, 172(2), 124–133. https://doi.org/10.1680/jstbu.17.00154

ASTM E 119-20. (2020). Standard test methods for fire tests of building construction and materials. ASTM International.

Aydin, F. (2018). Thermal effects on GFRP rebars: Experimental study and analytical analysis. Materials and Structures, 51(3), 59. https://doi.org/10.1617/s11527-018-1171-7

Djamaluddin, R., Irmawaty, R., Hamzah, S., & Ngeljaratan, L. N. (2023). Effect of bonding area on bond stress behavior of GFRP bars in concrete. Civil Engineering Journal, 9, 123–140.

El-Gamal, S. (2014). Bond strength of glass fiber-reinforced polymer bars in concrete after exposure to elevated temperatures. Journal of Reinforced Plastics and Composites, 33(9), 826–836. https://doi.org/10.1177/0731684413518764

Fava, G., Carvelli, V., & Pisani, M. A. (2016). Remarks on bond of GFRP rebars and concrete. Composites Part B: Engineering, 93, 210–220.

Granadeiro, L. M. R., Azevedo, F. S., & Teixeira, A. J. (2019). Experimental investigation of bond behaviour of two common GFRP bar types in high-strength concrete. Construction and Building Materials, 200, 757–765. https://doi.org/10.1016/j.conbuildmat.2018.12.030

Hajiloo, A., Green, M. F., & Faghih, M. (2018). Bond strength of GFRP reinforcing bars at high temperatures with implications for performance in fire. Journal of Composites for Construction, 22(3), 04018003. https://doi.org/10.1061/(ASCE)CC.1943-5614.0000837

Hussien, N., & Al-Thairy, H. (2020). Numerical study on the performance of GFRP RC beams exposed to high temperature. Al-Qadisiyah Journal of Engineering Sciences, 13, 136–143.

Jomaa'h, M. M., Salahaldin, A. I., Saber, Q. A., & Raheem, A. M. (2022). Large-scale laboratory setup for testing structural performance of slender high-strength concrete columns subjected to axial load and fire: A preliminary study. In Geotechnical Engineering and Sustainable Construction: Sustainable Geotechnical Engineering (pp. 611–626). Springer.

Katz, A., & Cohn, M. (2018). The effect of high temperature on the bond strength of GFRP bars in concrete. Composites Part B: Engineering, 138, 101–107. https://doi.org/10.1016/j.compositesb.2017.11.031

Kim, J., Jeong, S., Kim, H., Kim, Y., & Park, S. (2022). Bond strength properties of GFRP and CFRP according to concrete strength. Applied Sciences, 12(20), 10611.

Maranan, G. B., Manalo, A. C., Karunasena, W., & Benmokrane, B. (2015). Pullout behaviour of GFRP bars with anchor head in geopolymer concrete. Composite Structures, 132, 1113–1121.

Masmoudi, R., & Masmoudi, A. (2010). Bond of GFRP bars in concrete: Experimental study and analytical interpretation. Journal of Composites for Construction, 14(2), 171–179. https://doi.org/10.1061/(ASCE)1090-0268(2010)14:2(171)

McIntyre, E. R., Bisby, L., & Stratford, T. (2014). Bond strength of FRP reinforcement in concrete at elevated temperature. In 7th International Conference on Fiber Reinforced Polymer (FRP) Composites in Civil Engineering (CICE 2014).

Mohammed, M. H. (2019). A review of bond behavior of glass fiber reinforced polymer bars with concrete. Journal of Engineering and Sustainable Development, 23(3), 142–157.

Najafabadi, E. P., Oskouei, A. V., & Khaneghahi, M. H. (2019). The tensile performance of FRP bars embedded in concrete under elevated temperatures. Construction and Building Materials, 215, 193–204. https://doi.org/10.1016/j.conbuildmat.2019.04.233

Özkal, F. M., Polat, M., Yağan, M. O., & Öztürk, M. (2018). Mechanical properties and bond strength degradation of GFRP and steel rebars at elevated temperatures. Construction and Building Materials, 176, 356–363. https://doi.org/10.1016/j.conbuildmat.2018.05.186

Rosa, I. C., Firmo, J. P., Correia, J. R., & Mazzuca, P. (2021). Influence of elevated temperatures on the bond behaviour of ribbed GFRP bars in concrete. Cement and Concrete Composites, 113, 103774. https://doi.org/10.1016/j.cemconcomp.2020.103774

Solyom, S., Di Benedetti, M., Guadagnini, M., & Gallo, M. (2020). Effect of temperature on the bond behaviour of GFRP bars in concrete. Composites Part B: Engineering, 190, 107943. https://doi.org/10.1016/j.compositesb.2020.107943

Zhao, J., Luo, X., Wang, Z., Feng, S., Gong, X., & Shumuye, E. D. (2021). Experimental study on bond performance of carbon- and glass-fiber reinforced polymer (CFRP/GFRP) bars and steel strands to concrete. Materials, 14(5), 1268.

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Published

2025-01-11

How to Cite

Ahmed Yahya Gaeeb, & Muayad Mohammed Kassim. (2025). An Experimental Research Into the Bonding Strength of GFRP Bars in Concrete Under Elevated Temperatures. International Journal of Mechanical, Electrical and Civil Engineering, 2(1), 122–137. https://doi.org/10.61132/ijmecie.v1i1.143