Comparative study on the tensile mechanical behavior of GFRP bars under and after high temperature exposure
Glass fiber-reinforced polymer (GFRP) bars are being increasingly used in reinforced concrete structures to replace ordinary steel reinforcements as an effective and economical solution to corrosion problems. The mechanical behavior of GFRP bars under and after high temperature exposure is crucial f...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Elsevier
2022-06-01
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| Series: | Case Studies in Construction Materials |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S2214509522000377 |
| _version_ | 1811336265955540992 |
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| author | Chunheng Zhou Jinjing Pan Zihua Zhang Yaohong Zhu |
| author_facet | Chunheng Zhou Jinjing Pan Zihua Zhang Yaohong Zhu |
| author_sort | Chunheng Zhou |
| collection | DOAJ |
| description | Glass fiber-reinforced polymer (GFRP) bars are being increasingly used in reinforced concrete structures to replace ordinary steel reinforcements as an effective and economical solution to corrosion problems. The mechanical behavior of GFRP bars under and after high temperature exposure is crucial for their application in structures potentially subjected to fire, and further research and comparisons are needed to increase the accuracy of fire-resistant design and post-fire analytical model of GFRP reinforced concrete members. Thus, this paper aimed to study the residual tensile performances of GFRP bars under and after high temperature exposure. The stress–strain curves, tensile strengths, elastic modulus, and ultimate strains of GFRP bar specimens while being subjected to, and after, different high temperatures were tested and compared. The effects of high temperature on the degradation mechanisms of GFRP bars were investigated using scanning electronic microscopy. The results showed that carbonization of resin and exposure of fibers in GFRP bars occurred gradually as the temperature increased. At the same temperature, the tensile failure modes and stress–strain relationships for specimens under and after high temperature were similar. However, the residual tensile strengths and ultimate strains on GFRP bars after high temperatures were greater than those under high temperatures, which ranged from 150 ℃ to 350 ℃, indicating that the different values of those mechanical properties should be taken into account in the analysis of fire resistance and the post-fire identification of concrete structures reinforced with GFRP bars. Finally, regressive models for the residual tensile strengths and elastic moduli of GFRP bars under and after high temperature exposure, respectively, were developed, based on the results of this experiment and previous studies. The calculated results correlated well with the experimental results. |
| first_indexed | 2024-04-13T17:36:55Z |
| format | Article |
| id | doaj.art-6479cb1df13d428291637bdaf7131eb6 |
| institution | Directory Open Access Journal |
| issn | 2214-5095 |
| language | English |
| last_indexed | 2024-04-13T17:36:55Z |
| publishDate | 2022-06-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Case Studies in Construction Materials |
| spelling | doaj.art-6479cb1df13d428291637bdaf7131eb62022-12-22T02:37:20ZengElsevierCase Studies in Construction Materials2214-50952022-06-0116e00905Comparative study on the tensile mechanical behavior of GFRP bars under and after high temperature exposureChunheng Zhou0Jinjing Pan1Zihua Zhang2Yaohong Zhu3School of Civil and Environmental Engineering, Ningbo University, 315211 Ningbo, China; Correspondence to: No. 818 Fenghua Road, Ningbo, Zhejiang 315211, China.School of Civil and Environmental Engineering, Ningbo University, 315211 Ningbo, ChinaSchool of Civil and Environmental Engineering, Ningbo University, 315211 Ningbo, ChinaCollaborative Innovation Center of Coastal Urban Rail Transit, Ningbo University, 315211 Ningbo, China; Correspondence to: No. 818 Fenghua Road, Ningbo, Zhejiang 315211, China.Glass fiber-reinforced polymer (GFRP) bars are being increasingly used in reinforced concrete structures to replace ordinary steel reinforcements as an effective and economical solution to corrosion problems. The mechanical behavior of GFRP bars under and after high temperature exposure is crucial for their application in structures potentially subjected to fire, and further research and comparisons are needed to increase the accuracy of fire-resistant design and post-fire analytical model of GFRP reinforced concrete members. Thus, this paper aimed to study the residual tensile performances of GFRP bars under and after high temperature exposure. The stress–strain curves, tensile strengths, elastic modulus, and ultimate strains of GFRP bar specimens while being subjected to, and after, different high temperatures were tested and compared. The effects of high temperature on the degradation mechanisms of GFRP bars were investigated using scanning electronic microscopy. The results showed that carbonization of resin and exposure of fibers in GFRP bars occurred gradually as the temperature increased. At the same temperature, the tensile failure modes and stress–strain relationships for specimens under and after high temperature were similar. However, the residual tensile strengths and ultimate strains on GFRP bars after high temperatures were greater than those under high temperatures, which ranged from 150 ℃ to 350 ℃, indicating that the different values of those mechanical properties should be taken into account in the analysis of fire resistance and the post-fire identification of concrete structures reinforced with GFRP bars. Finally, regressive models for the residual tensile strengths and elastic moduli of GFRP bars under and after high temperature exposure, respectively, were developed, based on the results of this experiment and previous studies. The calculated results correlated well with the experimental results.http://www.sciencedirect.com/science/article/pii/S2214509522000377Glass fiber-reinforced polymer barsHigh temperatureTensile strengthElastic modulusExperimental tests |
| spellingShingle | Chunheng Zhou Jinjing Pan Zihua Zhang Yaohong Zhu Comparative study on the tensile mechanical behavior of GFRP bars under and after high temperature exposure Case Studies in Construction Materials Glass fiber-reinforced polymer bars High temperature Tensile strength Elastic modulus Experimental tests |
| title | Comparative study on the tensile mechanical behavior of GFRP bars under and after high temperature exposure |
| title_full | Comparative study on the tensile mechanical behavior of GFRP bars under and after high temperature exposure |
| title_fullStr | Comparative study on the tensile mechanical behavior of GFRP bars under and after high temperature exposure |
| title_full_unstemmed | Comparative study on the tensile mechanical behavior of GFRP bars under and after high temperature exposure |
| title_short | Comparative study on the tensile mechanical behavior of GFRP bars under and after high temperature exposure |
| title_sort | comparative study on the tensile mechanical behavior of gfrp bars under and after high temperature exposure |
| topic | Glass fiber-reinforced polymer bars High temperature Tensile strength Elastic modulus Experimental tests |
| url | http://www.sciencedirect.com/science/article/pii/S2214509522000377 |
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