Life Cycle Cost GA Optimization of Repaired Reinforced Concrete Structures Located in a Marine Environment

Document Type : Regular Article


Assistant Professor, Department of Civil Engineering, Tafresh University, Tafresh, Iran


Life-Cycle-Cost (LCC) analysis of corroded structures located in corrosive marine environments considers the time-dependent resistance and loading affect, and repair and maintenance scenarios applied during life time of these structures. Finding the optimum repair and maintenance scenario for a corroded reinforced concrete (RC) structure is a significant process to select a repair and maintenance scenario with minimum LCC and maximum service lifetime. For this purpose, a finite element (FE) model is applied to assess the time-dependent capacity of corroded RC circular column using nonlinear analysis. In corrosion initiation phase, empirical chloride diffusion and surface chloride concentration models obtained for silica fume RC under long-term exposure in splash zone of Bandar-Abbas coasts, located in south side of Iran, and in corrosion propagation phase, empirical corrosion current density model for splash zone of a marine environment in literature is used for modeling of corrosion process. In this analysis, the influence of a number of repair or rehabilitation scenarios on the performance of a corroded circular RC column due to chloride-induced corrosion, including five different concrete surface coatings used on the external surface of concrete, four different increasing concrete cover thickness and using the new longitudinal and horizontal reinforcements after the initial cracking of concrete cover are investigated. These 11 different scenarios with considering a scenario without any repair are optimized by Genetic Algorithm (GA) based on minimum LCC cost and 40 years failure time in terms of corrosion.


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[1]     Xie J, Hu R. Experimental study on rehabilitation of corrosion-damaged reinforced concrete beams with carbon fiber reinforced polymer. Constr Build Mater 2013;38:708–16. doi:10.1016/j.conbuildmat.2012.09.023.
[2]     Vaysburd AM, Emmons PH. Corrosion inhibitors and other protective systems in concrete repair: concepts or misconcepts. Cem Concr Compos 2004;26:255–63. doi:10.1016/S0958-9465(03)00044-1.
[3]     Alizadeh R, Ghods P, Chini M, Hoseini M, Ghalibafian M, Shekarchi M. Effect of Curing Conditions on the Service Life Design of RC Structures in the Persian Gulf Region. J Mater Civ Eng 2008;20:2–8. doi:10.1061/(ASCE)0899-1561(2008)20:1(2).
[4]     Guzmán S, Gálvez JC. Modelling of concrete cover cracking due to non-uniform corrosion of reinforcing steel. Constr Build Mater 2017;155:1063–71. doi:10.1016/j.conbuildmat.2017.08.082.
[5]     Ehlen MA. Life-365TM Service Life Prediction ModelTM and computer program for predicting the service life and life-cycle cost of reinforced concrete exposed to chlorides. Manual of Life-365TM Version 2.1, Produced by the Life-365TM Consortium II. 2012.
[6]     de Vera G, Climent MA, Viqueira E, Antón C, Andrade C. A test method for measuring chloride diffusion coefficients through partially saturated concrete. Part II: The instantaneous plane source diffusion case with chloride binding consideration. Cem Concr Res 2007;37:714–24. doi:10.1016/j.cemconres.2007.01.008.
[7]     Farahani A, Shekarchi M. Time-Dependent Structural Behavior of Repaired Corroded RC Columns Located in a Marine Site. J Rehabil Civ Eng 2020;8:40–9.
[8]     Khaghanpour R, Dousti A, Shekarchi M. Prediction of Cover Thickness Based on Long-Term Chloride Penetration in a Marine Environment. J Perform Constr Facil 2017;31:04016070. doi:10.1061/(ASCE)CF.1943-5509.0000931.
[9]     Tadayon MH, Shekarchi M, Tadayon M. Long-term field study of chloride ingress in concretes containing pozzolans exposed to severe marine tidal zone. Constr Build Mater 2016;123:611–6. doi:10.1016/j.conbuildmat.2016.07.074.
[10]    Cheewaket T, Jaturapitakkul C, Chalee W. Effect of Fly Ash on Chloride Penetration and Compressive Strength of Reclycled and Natural Aggregate Concrete under 5-year Exposure in Marine Environment. J King Mongkut’s Univ Technol North Bangkok 2019;29:112–23.
[11]    Ožbolt J, Oršanić F, Balabanić G. Modelling processes related to corrosion of reinforcement in concrete: coupled 3D finite element model. Struct Infrastruct Eng 2017;13:135–46. doi:10.1080/15732479.2016.1198400.
[12]    Otieno M, Beushausen H, Alexander M. Resistivity-based chloride-induced corrosion rate prediction models and hypothetical framework for interpretation of resistivity measurements in cracked RC structures. Mater Struct 2016;49:2349–66. doi:10.1617/s11527-015-0653-z.
[13]    Kong Q, Gong G, Yang J, Song X. The corrosion rate of reinforcement in chloride contaminated concrete. Low Temp Archit Technol 2006;111:1–2.
[14]    Vu KAT, Stewart MG. Structural reliability of concrete bridges including improved chloride-induced corrosion models. Struct Saf 2000;22:313–33. doi:10.1016/S0167-4730(00)00018-7.
[15]    Cho SH, Chung L, Roh Y-S. Estimation of Rebar Corrosion Rage in Reinforced Concrete Structure. Corros Rev 2005;23:329–54.
[16]    Cheng M-Y, Chiu Y-F, Chiu C-K, Prayogo D, Wu Y-W, Hsu Z-L, et al. Risk-based maintenance strategy for deteriorating bridges using a hybrid computational intelligence technique: a case study. Struct Infrastruct Eng 2019;15:334–50. doi:10.1080/15732479.2018.1547767.
[17]    Khanzadeh Moradllo M, Shekarchi M, Hoseini M. Time-dependent performance of concrete surface coatings in tidal zone of marine environment. Constr Build Mater 2012;30:198–205. doi:10.1016/j.conbuildmat.2011.11.044.
[18]    Yanaka M, Hooman Ghasemi S, Nowak AS. Reliability-based and life-cycle cost-oriented design recommendations for prestressed concrete bridge girders. Struct Concr 2016;17:836–47. doi:10.1002/suco.201500197.
[19]    Holland JH. Adaptation in natural and artificial systems: an introductory analysis with applications to biology, control, and artificial intelligence. MIT press; 1992.
[20]    Goldberg DE, Holland JH. Genetic algorithms and machine learning. 3(2):95-99. Kluwer Academic Publishers-Plenum Publishers; 1988.
[21]    Farahani A, Taghaddos H, Shekarchi M. Influence of Repair on Corrosion Failure Modes of Square RC Columns Located in Tidal Zone. J Perform Constr Facil 2020;Accepted.
[22]    Afsar Dizaj E, Madandoust R, Kashani MM. Exploring the impact of chloride-induced corrosion on seismic damage limit states and residual capacity of reinforced concrete structures. Struct Infrastruct Eng 2018;14:714–29. doi:10.1080/15732479.2017.1359631.
[23]    Hazus -MH MR5. Advanced Engineering Building Module (AEBM). Department of Homeland, Security Federal Emergency Management Agency, Mitigation Division, Washington. n.d.
[24]    Farahani A, Taghaddos H, Shekarchi M. Prediction of long-term chloride diffusion in silica fume concrete in a marine environment. Cem Concr Compos 2015;59:10–7. doi:10.1016/j.cemconcomp.2015.03.006.
[25]    Tadayon MM. Modeling Reinforcement Corrosion Initiation & Propagation for Life Time Estimation of Concrete Structures in Persian Gulf Environment. Ph.D. Thesis, University of Tehran, School of Civil Engineering, Tehran, Iran., 2018.
[26]    Vidal T, Castel A, François R. Analyzing crack width to predict corrosion in reinforced concrete. Cem Concr Res 2004;34:165–74. doi:10.1016/S0008-8846(03)00246-1.
[27]    Liu Y, Weyers RE. Modeling the time-to-corrosion cracking in chloride contaminated reinforced concrete structures. ACI Mater J n.d.;95:675–81.
[28]    Val D V. Factors affecting life-cycle cost analysis of RC structures in chloride contaminated environments. J Infrastruct Syst 2007;13:135–43. doi:10.1061/(ASCE)1076-0342(2007)13:2(135).