Properties of GFRP Bars Subjected to High Temperature
Received: 24 November 2024 | Revised: 9 December 2024 | Accepted: 19 December 2024 | Online: 2 February 2025
Corresponding author: Maan Hatam Saeed
Abstract
This study evaluates the properties of Glass Fiber Reinforced Polymer (GFRP) bars exposed to high temperatures. An experimental program was carried out, which investigated 30 samples burned at different temperatures, 300 °C, 500 °C, and 700 °C, and compared them with additional unburned samples. The chosen parameters in this study consist of the concrete cover thickness and the burning temperature. The experimental results demonstrated that at a temperature of 300 °C, burning did not significantly affect the tensile strength of the covered samples, as it exhibited a decrease between 0% and 7%. In contrast, at a temperature of 500 °C, burning significantly influenced the specific samples’ tensile strength, as its decrease ranged between 0 and 30%. At 700 °C, burning substantially impacted the covered samples’ tensile strength, causing a reduction ranging from 2% to 58%, contingent on the concrete cover thickness. It was generally observed that the samples’ tensile strength decreased as the burning temperature increased, and that although significant alterations in the tensile characteristics of the uncoated GFRP bars were noted at 300 °C, the critical threshold for the coated GFRP bars was identified around 500 °C.
Keywords:
concrete cover, elevated temperature, fire, GFRP bars, burningDownloads
References
A. F. Hallawi and A. H. A. Al-Ahmed, "Enhancing the Behavior of One-Way Reinforced Concrete Slabs by Using Laced Reinforcement," Civil Engineering Journal, vol. 5, no. 3, pp. 718–728, Mar. 2019.
A. H. A. Al-Ahmed, A. H. Al-Zuhairi, and A. M. Hasan, "Behavior of reinforced concrete tapered beams," Structures, vol. 37, pp. 1098–1118, Mar. 2022.
Z. K. Al-Mamory and A. H. A. Al-Ahmed, "Behavior of steel fiber reinforced concrete beams with CFRP wrapped lap splice bars," Structures, vol. 44, pp. 1995–2011, Oct. 2022.
B. F. Abdulkareem, A. F. Izzet, and N. Oukaili, "Post-Fire Behavior of Non-Prismatic Beams with Multiple Rectangular Openings Monotonically Loaded," Engineering, Technology & Applied Science Research, vol. 11, no. 6, pp. 7763–7769, Dec. 2021.
M. Abdulkhaliq and A. H. Al-Ahmed, "Behavior of GFRP Reinforced-Concrete Bubbled One-Way Slabs by Encased Composite Steel I-Sections," Engineering, Technology & Applied Science Research, vol. 14, no. 5, pp. 16701–16712, Oct. 2024.
B. F. Abdulkareem and A. F. Izzet, "Post Fire Residual Concrete and Steel Reinforcement Properties," IOP Conference Series: Earth and Environmental Science, vol. 856, no. 1, Jun. 2021, Art. no. 012058.
S. Alsayed, Y. Al-Salloum, T. Almusallam, S. El-Gamal, and M. Aqel, "Performance of glass fiber reinforced polymer bars under elevated temperatures," Composites Part B: Engineering, vol. 43, no. 5, pp. 2265–2271, Jul. 2012.
S. El-Gamal, "Bond strength of glass fiber-reinforced polymer bars in concrete after exposure to elevated temperatures," Journal of Reinforced Plastics and Composites, vol. 33, no. 23, pp. 2151–2163, Dec. 2014.
H. Hajiloo, M. F. Green, and J. Gales, "Mechanical properties of GFRP reinforcing bars at high temperatures," Construction and Building Materials, vol. 162, pp. 142–154, Feb. 2018.
F. M. Özkal, M. Polat, M. Yağan, and M. O. Öztürk, "Mechanical properties and bond strength degradation of GFRP and steel rebars at elevated temperatures," Construction and Building Materials, vol. 184, pp. 45–57, Sep. 2018.
F. Aslani, "Residual bond between concrete and reinforcing GFRP rebars at elevated temperatures," Proceedings of the Institution of Civil Engineers - Structures and Buildings, vol. 172, no. 2, pp. 127–140, Feb. 2019.
I. C. Rosa, J. P. Firmo, J. R. Correia, and P. Mazzuca, "Influence of elevated temperatures on the bond behaviour of ribbed GFRP bars in concrete," Cement and Concrete Composites, vol. 122, Sep. 2021, Art. no. 104119.
I. C. Rosa, J. P. Firmo, and J. R. Correia, "Experimental study of the tensile behaviour of GFRP reinforcing bars at elevated temperatures," Construction and Building Materials, vol. 324, Mar. 2022, Art. no. 126676.
Fibre-reinforced polymer (FRP) reinforcement of concrete — Test methods — Part 1: FRP bars and grids, 2nd ed. ISO, 2015.
F. Aslani, "Prestressed concrete thermal behaviour," Magazine of Concrete Research, vol. 65, no. 3, pp. 158–171, Feb. 2013.
F. Yang and P. Yao, "Effect of temperature on tensile mechanical properties of GFRP bars with different diameters," IOP Conference Series: Earth and Environmental Science, vol. 189, no. 3, Aug. 2018, Art. no. 032068.
C. Zhou, J. Pan, Z. Zhang, and Y. Zhu, "Comparative study on the tensile mechanical behavior of GFRP bars under and after high temperature exposure," Case Studies in Construction Materials, vol. 16, Jun. 2022, Art. no e00905.
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