Corrosion Mechanisms in Reinforced Concrete: Causes, Effects, and Sustainable Mitigation Strategies

Corrosion in reinforced concrete (RC) structures is a serious concern in civil engineering, influencing durability, structural integrity, and maintenance costs. This research covers the principal corrosion processes, including carbonation-induced and chloride-induced corrosion, which erode reinforcement and impair the lifetime of RC structures. Carbonation lowers concrete alkalinity, weakening the passive layer on steel, while chloride penetration causes localized pitting corrosion, leading to fast degradation. Key environmental and material elements impacting corrosion advancement, such as concrete permeability, water-to-cement ratio, exposure circumstances, and cyclic wet-dry environments, are investigated. Corrosion-induced mechanical deterioration, including cracking, loss of reinforcement cross-section, and bond strength reduction, is also examined. The study analyzes mitigating measures, stressing the significance of supplemental cementitious materials (SCMs) such as silica fume, fly ash, and ground granulated blast furnace slag (GGBFS), which increase durability by lowering permeability and chloride diffusion. Additional preventive approaches, including corrosion inhibitors, epoxy-coated rebars, cathodic protection, and improved design codes, are explored. Advanced corrosion monitoring technologies, including non-destructive testing (NDT) methodologies and machine learning-based prediction models, offer new options for early corrosion identification and efficient maintenance planning. Findings reveal that combining corrosion-resistant materials with proactive maintenance procedures and real-time monitoring can greatly increase the service life of RC structures while lowering long-term repair costs. This work adds to creating sustainable and cost-effective corrosion mitigation technologies, giving significant information for researchers, engineers, and infrastructure managers.