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A Mathematical Model of Flexural-Creep Behaviour for Future Service Expectancy of a GFRP Composite Cross-Arm with the Influence of Outdoor Temperature

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Abstract

Exposure to high temperatures can damage GFRP laminates’ mechanical properties and, as a result, degrade their long-term performance, leading to rupture during their service life. Therefore, this study investigated the flexural-creep behaviour of pultruded glass fibre-reinforced polymer (pGFRP) when subjected to elevated temperatures and utilised two mathematical models to evaluate the structure's serviceability when subjected to a variety of stress levels. Two main parameters were investigated: elevated temperature (25 to 40 °C) and constant load levels (12%, 24%, and 37%), whereas the pGFRP specimens were monitored for 720 h (30 days). Furthermore, the experimental work has been paired with mathematical models, namely, Findley’s power law model and Burger’s model, to predict the life span of a pGFRP cross-arm according to the data obtained from creep tests. Results showed the specimens failed in a brittle manner as expected under the static 4-point bending tests with an average ultimate strength of 242.6 MPa. Moreover, both models used to simulate the creep behaviour of the GFRP laminates matched very well with the experimental data. However, these models showed a substantial difference in the strain predicted over the 120,000 h period, with Burger’s model predicting the specimens to reach the ultimate strain in 9.4 to 11.4 years, depending on the stress level, while Findley’s model only showed a minimal increase in the total strain. This suggests that Burger’s model might be more conservative and more reasonable for creep at elevated temperatures.

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Data availability

The data that support the findings of this study are available on request from the corresponding author, [Agusril@uniten.edu.my]. The data are not publicly available due to restrictions, as they contain sensitive information that could compromise the privacy and confidentiality of research participants. In order to protect the privacy rights of the participants, access to the data can only be granted upon request and after appropriate ethical approvals and data protection measures are in place.

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Acknowledgements

The authors are grateful to acknowledge the IRMC UNITEN and the Institute of Energy Infrastructure (IEI) for the financial support provided through BOLD 2022, through Project No: J510050002/2022004 research grant. The authors also acknowledge Tenaga Nasional Berhad (TNB) and UNITEN R & D for the lab facilities from the TNB Seeding Fund: U-TS-RD-21-10.

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Authors and Affiliations

  1. Civil Engineering Department, College of Engineering, Universiti Tenaga Nasional, 43000, Kajang, Malaysia

    Abdulrahman Alhayek, Agusril Syamsir & Fathoni Usman

  2. Institute of Energy Infrastructure (IEI), College of Engineering, Universiti Tenaga Nasional, 43000, Kajang, Malaysia

    Agusril Syamsir, A. B. M. Supian & M. I. Najeeb

  3. Centre for Advanced Composite Materials (CACM), Universiti Teknologi Malaysia, Johor Bahru, 81310, Johor, Malaysia

    M. R. M. Asyraf

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Alhayek, A., Syamsir, A., Supian, A.B.M. et al. A Mathematical Model of Flexural-Creep Behaviour for Future Service Expectancy of a GFRP Composite Cross-Arm with the Influence of Outdoor Temperature. Fibers Polym 24, 2425–2437 (2023). https://doi.org/10.1007/s12221-023-00235-3

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