Probabilistic assessment of silane impregnation and electrochemical chloride removal treatment on protection effect against steel corrosion in marine concrete structures

This paper concerns the protective performance of maintenance strategies, i.e. silane impregnation (SI) and electrochemical chloride extraction (ECE), against chloride-induced corrosion for concrete elements in marine environment. The effectiveness of SI treatment is researched through long-term exposure tests, and the efficiency of ECE treatment is considered using a quantitative expression. The failure probability evolution is calculated through reliability theory and Monte-Carlo simulations. The maintenance planning is established, and relevant maintenance costs are determined. The obtained results show that (1) the effective protection life of initially applied silane is longer than 12 years, but the protective performance of reapplied silane is not as pronounced as the silane initially applied; (2) the chloride ions at steel surface are efficiently removed after ECE which is more conducive to sustain the steel rebars free from corrosion; (3) ECE treatment attains the optimal cost and is recommended for long life-span concrete elements in marine environment.