Enhancing structural durability in marine concrete piles with initial defects: RS-AAT-induced advection to suppress chloride ion penetration

• Published in: Engineering structures 2024-12, Vol.321, p.118938, Article 118938
• Main Authors: He, Sihong, Xiao, Liang, Chen, Deqiang, Hou, Senlei, Mei, Guoxiong
• Format: Article
• Language: English
• Subjects: Centrifugal stratification; Chloride; Concrete structure; Crack; Durable life; RS-AAT
• ISSN: 0141-0296
• DOI: 10.1016/j.engstruct.2024.118938

Chlorine-induced corrosion in unsaturated, cracked, and delaminated reinforced concrete structures is a major cause of lifespan decline in marine wet and dry zones. Reverse-seepage and Saturation based Active Anti-corrosion Technology (RS-AAT) has the scientific basis and application potential to solve this problem due to its unique saturation and reverse-seepage effects provided by structural construction means. This study introduces an analytical framework for understanding time-dependent chloride ion permeation in concrete pipe piles, incorporating the combined impact of cracks, delamination, and RS-AAT anti-corrosion approach. The analytical approach is validated through finite element method simulations and a comprehensive 90-day indoor experiment, which simulate marine submerged and tidal conditions. Extensive parametric analysis further elucidates advection-induced suppression of chloride ion diffusion by RS-AAT in cracked and delaminated conditions, considering chloride ion diffusion coefficient and water permeability coefficient, reverse-seepage pressure, initial crack characteristics and centrifugal stratification. Results show that RS-AAT substantially inhibits chloride ion penetration and lengthens the lifespan of concrete piles, even initially cracked or delaminated. This work provides a basis for RS-AAT’s application and optimization as an innovative approach to enhancing marine concrete infrastructure. •The anti-chloride ingress properties of RC structure treated by a non-material approach (RS-AAT).•Advection-induced suppression of chloride ion diffusion in cracked and delaminated conditions.•Transport model combined with layered advection-diffusion model and Darcy's law.•Parameter analysis on seepage pressure, time-variable diffusion, and permeability coefficients.