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Influence of corrosion on reinforced concrete in chloride environments: Top-bar effect, steel fiber reinforcement and cracks
Abstract
Reinforced concrete (RC) is one of the most widely used construction materials due to its strength and durability. However, with time, RC structures may experience deterioration in quality and reduction in service life due to the corrosion of reinforcing steel. This study investigates the influence of corrosion behavior in chloride environments, considering the top-bar effect, the presence of steel fibers in concrete, and the existence of artificial cracks. RC specimens were cyclically exposed to a 35 g/L NaCl solution, while corrosion activity was monitored through galvanic current measurements, mass loss evaluations, and visual inspections of crack map and corrosion distribution. The results indicate that in steel-fiber-reinforced concrete, the initiation of corrosion-induced cracking occurs significantly later than in plain concrete. However, the addition of fibers does not allow to give an anodic control of corrosion. Notably, when the concrete cover is thin, the top-bar effect becomes the dominant factor, introducing micro-defects and weak interfaces at the steel–concrete boundary that facilitate chloride ingress. Consequently, the top-bar effect plays a more critical role than the presence of artificial cracks in controlling the initiation and propagation of corrosion. The results show that corrosion-induced cracks in steel fiber-reinforced concrete develop more slowly than in conventional concrete. The addition of fibers does not allow to give an anodic control of corrosion. Top-bar effect is more important than artificial crack in case of weak cover thickness.
References
- U. M. Angst, O. B. Isgor, C. M. Hansson, A. Sagüés, and M. R. Geiker, "Beyond the Clorua threshold concept for predicting corrosion of steel in concrete," Applied Physics Reviews, vol. 9, p. 011321, 2022. DOI: https://doi.org/10.1063/5.0076320
- J. Smith and Y. P. Virmani, "Materials and methods for corrosion control of reinforced and prestressed concrete structures in new construction," United States. Federal Highway Administration 2000.
- G. Glass and N. Buenfeld, "Clorua‐induced corrosion of steel in concrete," Progress in Structural Engineering and Materials, vol. 2, pp. 448-458, 2000. DOI: https://doi.org/10.1002/pse.54
- U. M. Angst, M. R. Geiker, A. Michel, C. Gehlen, H. Wong, O. B. Isgor, et al., "The steel–concrete interface," Materials and Structures, vol. 50, pp. 1-24, 2017.
- T. U. Mohammed, N. Otsuki, H. Hamada, and T. Yamaji, "Chloride-induced corrosion of steel bars in concrete with presence of gap at steel-concrete interface," Materials Journal, vol. 99, pp. 149-156, 2002.
- W. Zhang, L. Yu, and R. Francois, "Influence of top-casting-induced defects on the corrosion of the compressive reinforcement of naturally corroded beams under sustained loading," Construction and Building Materials, vol. 229, p. 116912, 2019. DOI: https://doi.org/10.1016/j.conbuildmat.2019.116912
- A. S. El-Dieb, "Mechanical, durability and microstructural characteristics of ultra-high-strength self-compacting concrete incorporating steel fibers," Materials & Design, vol. 30, pp. 4286-4292, 2009. DOI: https://doi.org/10.1016/j.matdes.2009.04.024
- G. Naidu Gopu and S. A. Joseph, "Corrosion Behavior of Fiber-Reinforced Concrete—A Review," Fibers, vol. 10, p. 38, 2022. DOI: https://doi.org/10.3390/fib10050038
- R. François, S. Laurens, and F. Deby, Corrosion and its consequences for reinforced concrete structures: Elsevier, 2018.
- K. Tuutti, Corrosion of steel in concrete: Cement-och betonginst., 1982. DOI: 10.14359/4471
- L. Yu, R. François, V. H. Dang, V. l'Hostis, and R. Gagné, "Development of chloride-induced corrosion in pre-cracked RC beams under sustained loading: Effect of load-induced cracks, concrete cover, and exposure conditions," Cement and Concrete Research, vol. 67, pp. 246-258, 2015. DOI: https://doi.org/10.1016/j.cemconres.2014.10.007
- R. François and G. Arliguie, "Influence of service cracking on reinforcement steel corrosion," Journal of Materials in Civil Engineering, vol. 10, pp. 14-20, 1998. DOI: https://doi.org/10.1061/(ASCE)0899-1561(1998)10:1(14)
- W. Zhang, R. François, and L. Yu, "Influence of load-induced cracks coupled or not with top-casting-induced defects on the corrosion of the longitudinal tensile reinforcement of naturally corroded beams exposed to chloride environment under sustained loading," Cement and Concrete Research, vol. 129, p. 105972, 2020. DOI: https://doi.org/10.1016/j.cemconres.2020.105972
- R. François and G. Arliguie, "Influence of service cracking on reinforcement steel corrosion," Journal of Materials in Civil Engineering, vol. 10, pp. 14-20, 1998. DOI: https://doi.org/10.1061/(ASCE)0899-1561(1998)10:1(14)
- L. Yu, R. François, V. H. Dang, V. l'Hostis, and R. Gagné, "Development of chloride-induced corrosion in pre-cracked RC beams under sustained loading: Effect of load-induced cracks, concrete cover, and exposure conditions," Cement and Concrete Research, vol. 67, pp. 246-258, 2015. DOI: https://doi.org/10.1016/j.cemconres.2014.10.007