PSI - Issue 64

Tom Molkens et al. / Procedia Structural Integrity 64 (2024) 1484–1491 Tom Molkens & Mona El-Hallak/ Structural Integrity Procedia 00 (2024) 000 – 000

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For all tests, there are noticeable differences at the beginning of the test. However, once the crack load is reached (dotted vertical Pcr line), there is a clear trend towards stable values. The mid-support always shows a lower load level, while the end-support points indicate a higher load level than the theoretical values, the result of moment redistribution. Figure 4 also illustrates the evolution of the redistribution factor during the test. It ranges between 70 and 80% for all the tests at the transition point between the first and second stages. It is worth noting that this value is only obtained by the slippage of the top reinforcement. This is very obvious in figure 4 (a, b, and c), while it is vague in Figure 4d and the deformations are less uniform. During the 3rd stage and reaching the same load level as at the transition point between the 1st and 2nd cycles the redistribution factor shows to be 5 to 10% lower than before and at failure, it is about 60%, except for figure 4b. 5. Conclusions Based on the test results, it is possible to postulate a redistribution factor of 0.80, but this only becomes apparent when the upper reinforcement slips. For reloading, values of 0.75 to 0.70 are found, falling to 0.60 for the failure of the specimens. With appropriate reinforcement detailing, moment redistribution can be used, although the durability of the structure should be monitored due to the increased cracking associated with the use of GFRP reinforcement, especially in combination with slip. Acknowledgments The support of Hakron is well appreciated for the delivery of the GFRP rebars, further on this research would not been possible without our lab technician Luc Willems and PhD researchers Jules Smits and Shana Van Hout. References Almahmood, H., Ashour, A. & Sheehan, T., 2020. Flexural behaviour of hybrid steel-GFRP reinforced concrete continuous T-beams. Composite Structures, 9 August, p. https://doi.org/10.1016/j.compstruct.2020.112802. Basa, N., Ulicevic, M. & Zejak, R., 2018. Experimental research of continuous concrete beams with GFRP reinforcement. Advances in Civil Engineering, 18 October, p. https://doi.org/10.1155/2018/6532723. Basa, N., Vukovic, N. K., Ulicevec, M. & Muhadinovic, M., 2020. Effectrs of internal fore redistribution on the limit stes of continuous beams with GFRP reinforcement. Applied Sciences, 8 June, p. doi:10.3390/app10113973. Benmokrane, B., Mousa, S., Mohamed, K. & Sayed-Ahmed, M., 2021. Physical, mecchanical and durability characteristics of newly developed thermoplastic GFRP bars for reinforcing structures. Construction and Building Materials, 16 January, 10.1016/j.conbuildmat.2020.122200. de Castro, J. & Keller, T., 2009. Design of robust and ductile FRP structures incorporating ductile adhesive joints. Composites: Part B, 13 October, pp. 148-156. EN 1992-1-1, 2005. Design of concrete structures - Partl 1-1: General rules and rules for buildings (+AC 2008). Brussels: CEN250. Fava, G., Carvelli, V. & Pisani, M. A., 2016. Remarks on bond of GFRP rebars and concrete. Composites: Part B, 18 March, pp. 210-220. fib Bulletin 40, 2017. FRP reinforcement in RC structures, Laussane: Fédération intenationale du béton. Grace, N. F., Soliman, A. K., Abdel-Sayed, G. & Saleh, K. R., 1998. Behaviour and ductility of simple and continuous reinforced beams. Journal of composites for construction, November, pp. 186-194. Lin, X. & Zhang, Y. X., 2013. Bond-slip behaviour of FRP-reinforced concrete beams. Construction and Building Materials, 9 April, p. 110-117. Mistretta, F., Puppio, M. L., Camata, G. & Nanni, A., 2023. Analytical and experimental shear evaluation of GFRP-reinforced concrete beams. Material and Structures, 3 November, pp. https://doi.org/10.1617/s11527-023-02256-z. Molkens, T. & Lauwens, K., 2023. Resilient properties of a GFRP=embedded reinforced concrete slab. Istanbul, fib. Peng, F., Cai, Y., Yi, W. & Xue, W., 2023. Shear behaviour of two-span continuous concrete deep beams reinforced with GFRP bars.. Engineering Structures, 29 May, p. https://doi.org/10.1016/j.engstruct.2023.116367. Preinstorfer, P. et al., 2022. Parametric design studies of mass-related global warming potential and construction costs of FRP-reinforced concrete infrastructure. Polymers, 12 June, p. https//doi.org/10.3390/polym14122383. Rahnam, S. M. & El-Salakawy, E., 2016. Moment redistribution of GFRP-RC continuous T-beams. London, Resilient Infrastructure. Santos, P., Laranja, G., França, P. M. & Correia, J. R., 2013. Ductility and moment redistribution capacity of multi-span T-section concrete beams reinforced with GFRP-bars. Construction and Building Materials, 23 February, pp. 949-961. Sbahieh, S., Rabie, M., Ebead, U. & Al-Ghamdi, S., 2022. The mechanical and environmental performance of fibre-reinforced polymers in concrete structures: Opportunities, challenges and future directions. Buildings, 9 September, p. https://doi.org/10.3390/buildings12091417.