Abstract
Superhydrophobic cementitious composites are promising candidates to effectively mitigate long-term performance deterioration of concrete buildings due to external water infiltration. However, conventional superhydrophobic modifications often reduce compressive strength. To address this, a carbon sequestered superhydrophobic mortar was developed through a combination of micro-/nano-structuring and surface energy modification, achieving water contact angles of 153°–162° and a 10 MPa increase in 28-day compressive strength. Preparation involved dissolving alkaline solids (carbide slag and decarbonized fly ash), producing carbonated fly ash (CFA) through co-mineralization reactions, and modifying with fluoroalkylsilane (FAS). Performance indicators studied included wettability, compressive strength, water absorption, anti-chloride ions penetration, frost resistance, and microstructure. Results indicated that higher CFA and FAS contents led to improved water repellency and improved durability. Compared to control mortar, the superhydrophobic mortar showed about a 70 % reduction in water absorption, an 80.84 % decrease in chloride ions diffusion coefficient, and minimal mass and modulus loss after freeze-thaw cycles. These outcomes suggest that synergistic interactions between CFA and FAS provide a durable and responsive alternative for infrastructure resilience.
Original language | English |
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Article number | 106167 |
Journal | Cement and Concrete Composites |
Volume | 163 |
DOIs | |
Publication status | Published - Oct 2025 |
Keywords
- Anti-chloride ions penetration
- Carbonated fly ash
- Fluoroalkylsilane
- Frost resistance
- Microstructure
- Superhydrophobic mortar
ASJC Scopus subject areas
- Building and Construction
- General Materials Science