Effect of corrosion on the strength reduction and stress–strain characteristics of thermo–mechanically treated steel bars exposed to an accelerated chloride–rich environment
DOI:
https://doi.org/10.15282/construction.v6i1.13486Keywords:
TMT Bars, Accelerated corrosion, Salinity, Marine structures, Stress–strain, Ultimate strengthAbstract
This study investigated the detrimental impact of corrosion on the mechanical properties of thermo–mechanically treated (TMT) steel bars, a material widely used in reinforced concrete structures. The primary objective was to identify a crucial threshold level for corrosion, indicating a potential loss of structural integrity. Additionally, this research quantitatively assessed the percentage reduction in tensile strength and the alteration of stress–strain characteristics of TMT steel bars as a function of corrosion intensity. An accelerated corrosion process was conducted by utilizing the TMT bar as an anode and a stainless–steel plate as a cathode within an artificial seawater environment to simulate long–term exposure to chloride–rich coastal conditions. Experimental results demonstrated a significant and non–linear degradation in mechanical performance. At 12% corrosion, yield and ultimate strength reductions of 19.69% and 19.78% were recorded, respectively—beyond this critical threshold, the bars failed to meet the minimum designated yield stress and ultimate strength specified in International Organization for Standardization (ISO) 6935 (Grade G72.5–500). The findings established empirical correlations between corrosion intensity and key mechanical parameters, highlighting that corrosion not only reduces cross–sectional area but also induces localized pitting and brittle fracture initiation sites, which disproportionately affect stress–strain response. Critically, the post–yield behavior was severely affected; corrosion led to a marked loss of ductility, a contraction of the plastic plateau, and a considerable decline in tensile strength. This research provides essential data for evaluating the residual safety and service life of deteriorating coastal concrete infrastructures.
Downloads
References
[1] S.A.O. Nair, P. Mohandoss, K. Ram, T. Adnan, and R.G. Pillai, “Mechanical characteristics of Quenched and Self-Tempered (QST or TMT) steel reinforcing bars used in concrete structures,” Construction and Building Materials, vol. 363, p. 129761, 2022, https://doi.org/10.1016/j.conbuildmat.2022.129761.
[2] F. Badkoobeh, H. Mostaan, M. Rafiei, H.R. Bakhsheshi-Rad, and F. Berto, “Microstructural Characteristics and Strengthening Mechanisms of Ferritic–Martensitic Dual-Phase Steels: A Review,” Metals, vol. 12, no. 1, p. 101, 2022, https://doi.org/10.3390/met12010101.
[3] M.O. Osta, A. Azeem, S. Rashid, M. Harun, and A. Hanif, “Marine Resilience: Understanding the Durability and Effects on Concrete Structures—A Comprehensive Review,” Arabian Journal for Science and Engineering, vol. 51, no. 4, pp. 3981–4006, 2025, https://doi.org/10.1007/s13369-025-10697-7.
[4] M.S.H. Mahi, T.A. Ridoy, and A.A. Sarder, “Corrosion Mechanisms in Reinforced Concrete: Causes, Effects, and Sustainable Mitigation Strategies,” Current Problems in Research, vol. 1, no. 1, pp. 52–66, 2025, https://doi.org/10.70028/cpir.v1i1.27.
[5] B. Tansel and K. Zhang, “Effects of saltwater intrusion and sea level rise on aging and corrosion rates of iron pipes in water distribution and wastewater collection systems in coastal areas,” Journal of Environmental Management, vol. 315, p. 115153, 2022, https://doi.org/10.1016/j.jenvman.2022.115153.
[6] G.P.V. Dalmora, E.P.B. Filho, A.A.M. Conterato, W.S. Roso, C.E. Pereira, and A. Dettmer, “Methods of corrosion prevention for steel in marine environments: A review,” Results in Surfaces and Interfaces, vol. 18, p. 100430, 2025, https://doi.org/10.1016/j.rsurfi.2025.100430.
[7] R.E. Melchers, “Corrosion at the Steel–Medium Interface,” Corrosion and Materials Degradation, vol. 5, no. 1, pp. 52–72, 2024, https://doi.org/10.3390/cmd5010003.
[8] F. Du, Z. Jin, C. Xiong et al., “Nanoindentation analysis of corrosion products and induced expansion stress in reinforced concrete exposed to marine environments,” Journal of Building Engineering, vol. 78, p. 107753, 2023, https://doi.org/10.1016/j.jobe.2023.107753.
[9] F. Tariq and P. Bhargava, “Stress–strain curves and mechanical properties of corrosion damaged super ductile reinforcing steel,” Structures, vol. 33, pp. 1532–1543, 2021, https://doi.org/10.1016/j.istruc.2021.05.039.
[10] A.E. Udounwa and E.O. Wilson, “Corrosion of thermo-mechanically treated (TMT) mild steel in reinforced concrete structures: Mechanical and structural implications,” Journal of Applied Ecology and Environmental Design, vol. 9, no. 4, pp. 63–75, 2025, https://doi.org/10.70382/hujaeed.v9i4.009.
[11] M.R. Akhond, A. Irfan, and A. Sharif, “An overview of corrosion behavior and contemporary management techniques of thermo-mechanically treated rebars in concrete structures,” Journal of Structural Integrity and Maintenance, vol. 9, no. 1, p. 2259721, 2023, https://doi.org/10.1080/24705314.2023.2259721.
[12] S. Afkhami, K. Lipiäinen, V. Javaheri, M. Amraei, A. Salminen, and T. Björk, “Effects of notch-load-defect interactions on the local stress-strain fields and strain hardening of additively manufactured 18Ni300 steel,” Materials Science and Engineering A, vol. 876, p. 145165, 2023, https://doi.org/10.1016/j.msea.2023.145165.
[13] S. Cheng, J. Han, and J. Shang, “Optimal repair decision and seismic resilience analysis of seismic-damaged RC structures considering rebar corrosion,” Journal of Building Engineering, vol. 112, p. 113749, 2025, https://doi.org/10.1016/j.jobe.2025.113749.
[14] A. Lakshmi, P. Pandit, G. Nayak, Y. Bhagwat, and S. Kumar, “Influence of corrosion-based section loss on morphology and tensile capacity of pre-stressing strands,” Journal of Structural Integrity and Maintenance, vol. 9, no. 1, p. 2302655, 2024, https://doi.org/10.1080/24705314.2024.2302655.
[15] R.L. Riyar, D. Durgaprasad, T. Patel, and S. Bhowmik, “Influence of corrosion and reinforcement ratio on fracture performance of lightly reinforced concrete,” Progress in Engineering Science, vol. 2, no. 2, p. 100081, 2025, https://doi.org/10.1016/j.pes.2025.100081.
[16] K. Woloszyk, Y. Garbatov, and J. Kowalski, “Indoor accelerated controlled corrosion degradation test of small-and large-scale specimens,” Ocean Engineering, vol. 241, p. 110039, 2021, https://doi.org/10.1016/j.oceaneng.2021.110039.
[17] Y. Ou, Y.T.T. Susanto, and H. Roh, “Tensile behavior of naturally and artificially corroded steel bars,” Construction and Building Materials, vol. 103, pp. 93–104, 2015, https://doi.org/10.1016/j.conbuildmat.2015.10.075.
[18] M.T. Walsh and A.A. Sagüés, “Steel corrosion in submerged concrete structures—Part 1: field observations and corrosion distribution modelling,” Corrosion, vol. 72, no. 4, pp. 518–533, 2016, https://doi.org/10.5006/1945.
[19] E.M. Fernández, A.C. Escamilla, and M.F. Cánovas, “Ductility of reinforcing steel with different degrees of corrosion and the ‘equivalent steel’ criterion,” Materiales De Construcción, vol. 57, no. 286, pp. 5–18, 2007, https://doi.org/10.3989/mc.2007.v57.i286.43.
[20] R.E. Melchers, “Modelling immersion corrosion of structural steels in natural fresh and brackish waters,” Corrosion Science, vol. 48, no. 12, pp. 4174–4201, 2006, https://doi.org/10.1016/j.corsci.2006.04.012.
[21] C.A. Apostolopoulos and V.G. Papadakis, “Consequences of steel corrosion on the ductility properties of reinforcement bar,” Construction and Building Materials, vol. 22, no. 12, pp. 2316–2324, 2007, https://doi.org/10.1016/j.conbuildmat.2007.10.006.
[22] I. Fernandez, K. Lundgren, and K. Zandi, “Evaluation of corrosion level of naturally corroded bars using different cleaning methods, computed tomography, and 3D optical scanning,” Materials and Structures, vol. 51, no. 3, p. 78, 2018, https://doi.org/10.1617/s11527-018-1206-z.
[23] C.G. Berrocal, I. Fernandez, K. Lundgren, and I. Löfgren, “Corrosion-induced cracking and bond behaviour of corroded reinforcement bars in SFRC,” Composites Part B Engineering, vol. 113, pp. 123–137, 2017, https://doi.org/10.1016/j.compositesb.2017.01.020.
[24] K. Lundgren, M. Tahershamsi, K. Zandi, and M. Plos, “Tests on anchorage of naturally corroded reinforcement in concrete,” Materials and Structures, vol. 48, no. 7, pp. 2009–2022, 2014, https://doi.org/10.1617/s11527-014-0290-y.
[25] S.K. Durgam, G. Das, and A.K. Singh, “Corrosion effects of Cr and Ni in thermo-mechanical treated steel bar in marine environments,” International Research Journal of Engineering and Technology, vol. 4, no. 7, pp. 870–875, 2017.
[26] W. Zhu, R. François, C.S. Poon, and J.G. Dai, “Influences of corrosion degree and corrosion morphology on the ductility of steel reinforcement,” Construction and Building Materials, vol. 148, pp. 297–306, 2017, https://doi.org/10.1016/j.conbuildmat.2017.05.079.
[27] W. Zhu and R. François, “Experimental investigation of the relationships between residual cross-section shapes and the ductility of corroded bars,” Construction and Building Materials, vol. 69, pp. 335–345, 2014, https://doi.org/10.1016/j.conbuildmat.2014.07.059.
[28] G.H. Ahmed, G.B. Jumaa, N.H. Askandar, and A.S. Ali, “Degradation mechanisms and residual mechanical properties of reinforcing steel bars exposed to natural and artificial corrosion–Review & analysis,” Polytechnic Journal, vol. 12, no. 2, pp. 70–84, 2023, https://doi.org/10.25156/ptj.v12n2y2022.pp70-84.
[29] D. Wu, Y. Ding, J. Su, Z.X. Li, and B. Zhao, “Experimental investigation into corrosion effect on buckling and low-cycle fatigue performance of high-strength steel bars,” Engineering Structures, vol. 312, p. 118230, 2024, https://doi.org/10.1016/j.engstruct.2024.118230.
[30] M. Mohshin and M.N. Bari, “Optimal corrosion of TMT steel bars exposed to marine environment for structural safety assessment,” AIP Conference Proceedings, vol. 2713, p. 060001, 2023, https://doi.org/10.1063/5.0130056.
[31] M.N. Bari and M. Mohshin, “Relationship between rate of corrosion of TMT bars and quality of electrolyte in electrochemical corrosion process,” in Lecture notes in civil engineering, 2024, pp. 337–346. https://doi.org/10.1007/978-981-99-3826-1_28.
[32] J.A.P. Nicacio, F.C. Oliveira, and M.R. Dumont, “Failure analysis and electrochemical testing of ammonium chloride corrosion in a heat exchanger in a diesel hydrotreating unit of a petroleum refinery,” Engineering Failure Analysis, vol. 156, p. 107758, 2023, https://doi.org/10.1016/j.engfailanal.2023.107758.
[33] E. Mokhtari, A. Heidarpour, and F. Javidan, “Mechanical performance of high strength steel under corrosion: A review study,” Journal of Constructional Steel Research, vol. 220, p. 108840, 2024, https://doi.org/10.1016/j.jcsr.2024.108840.
[34] Y. Li, S. Zheng, L. Dong, D. Wang, Z. Sang, and G. Wen, “Mechanical properties of corroded steel bars on the tensile and buckling considering stirrup constraints,” Construction and Building Materials, vol. 417, p. 135181, 2024, https://doi.org/10.1016/j.conbuildmat.2024.135181.
[35] A.A. Almusallam, “Effect of degree of corrosion on the properties of reinforcing steel bars,” Construction and Building Materials, vol. 15, no. 8, pp. 361–368, 2001, https://doi.org/10.1016/s0950-0618(01)00009-5.
[36] J.K. Saha, R. Samanta, G. Mandal, M. Yadav, and S.K. Ghosh, “Experimental analysis of TMT bar and cold-drawn plain carbon steel spot welded mesh,” Sadhana, vol. 49, no. 4, p. 300, 2024, https://doi.org/10.1007/s12046-024-02636-3.
[37] Y. Zhang, T. Yan, L. Fan, Z. Liu, L. Song, and X. Li, “Effect of pH on the Corrosion and Repassivation Behavior of TA2 in Simulated Seawater,” Materials, vol. 14, no. 22, p. 6764, 2021, https://doi.org/10.3390/ma14226764.
[38] E. Chen, C.G. Berrocal, I. Löfgren, and K. Lundgren, “Correlation between concrete cracks and corrosion characteristics of steel reinforcement in pre-cracked plain and fibre-reinforced concrete beams,” Materials and Structures, vol. 53, no. 2, p. 33, 2020, https://doi.org/10.1617/s11527-020-01466-z.
Downloads
Published
Issue
Section
License
Copyright (c) 2026 The Author(s)
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
