Mechanical–transport–chemical modeling of electrochemical repair methods for corrosion-induced cracking in marine concrete

Reinforced concrete structures exposed to marine environments often experience chloride ingress, reinforcement corrosion, and corrosion-induced cracking. The electrochemical repair method is a promising concrete rehabilitation technique with advantages of non-destructive and economic performance in crack repair, chloride removal, and corrosion protection, which is particularly suitable for structures exposed to marine environments. This work presents an innovative methodology for modeling the mechanical, transport, and chemical process during electrochemical treatment for marine concrete structures. The entire process from concrete cracking up to repairing can be successfully reproduced and digitally visualized. The first sub-model calculates the corrosion-induced cracking process at the mesoscopic level with the consideration of local mechanical variances of concrete composites. Then, a reactive transport sub-model is established to reveal the interactions and electrochemical reactions among various species of ions. A crack repair sub-model is built to visualize the moving interface between chemical deposition and crack surface. Through combining the three sub-models, the interconnected influencing factors in practical engineering can be quantitively investigated. The calculation results show that, compared with electrolyte concentration, the influence of current density on crack closure rates are more obvious. Other factors such as steel reinforcement diameter and crack distribution pattern, which have not been previously reported are highlighted. These findings can guide the application of electrochemical repair in practical engineering.