PSI - Issue 67

Gabriele Milone et al. / Procedia Structural Integrity 67 (2025) 90–106 G. Milone et al./ Structural Integrity Procedia 00 (2024) 000 – 000

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Figure 13. (a,c,e) longitudinal and (b,d,f) transversal cross-sectional areas of fully corroded mortar beam with varying epoxy-based confinements at the rebar level: (a,b) 4 cm; (c,d) 8 cm; (e,f) 12 cm. Transversal cross-sections from below the coating application area. Longitudinal cross sections highlight a certain inefficacy of epoxy to perfectly seal the steel rebar from the mortar matrix. The investigation of specimens with partially confined rebar revealed some differences in corrosion dynamics and sensor responsiveness compared to fully exposed settings. This setup aimed to explore the effects that physical constraints had on corrosion propagation. Despite the epoxy's partial ineffectiveness in sealing the rebar, smart coatings effectively monitored corrosion-induced strain and damage, demonstrating their adaptability across different scenarios. Further studies should focus on distinguishing corrosion-driven damage from mechanical load-induced damage, to combine the two into a more comprehensive self-sensing analysis. 4. Conclusions This study presented an advancement in the field of smart construction materials, focusing on the development and application of carbon black (CB)-based cementitious coatings for corrosion sensing in reinforced concrete structures. This research highlighted the potential of smart coatings as multifunctional systems capable of early corrosion detection and monitoring. The accelerated corrosion tests, aimed at replicating critical chloride-induced scenarios, demonstrated the coatings' sensitivity and reliability in practical applications. By incorporating 2% NaCl by weight of cement and employing a constant galvanostatic current, the experiments achieved a controlled and predictable corrosive protocol. This setup not only facilitated a comprehensive understanding of the corrosion process but also allowed for the precise evaluation of the coatings' response to various stages of corrosion progression. Nonetheless, this setup encountered a strong limitation in the high randomness of oxide movements within the mortar matrix.