CNT-enhanced concrete: a shield against chemical attack

Purpose Concrete structures exposed to chemically aggressive environments, such as those containing acids, sulfates and chlorides, experience premature deterioration, reduced durability and increased maintenance costs. This study aims to improve the chemical resistance and microstructural integrity of concrete through the incorporation of multi-walled carbon nanotubes (CNTs) as nano-reinforcements. Design/methodology/approach CNTs were incorporated into the cement matrix at varying weight fractions of 0.25%, 0.5%, 0.75% and 1.0% by weight of cement. Specimens were exposed to simulated aggressive environments containing sulfuric acid. Experimental investigations included compressive strength testing, water absorption measurements and chemical resistance assessments, supported by microstructural analyses using scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy-dispersive X-ray (EDX) analysis. Findings The results demonstrated that CNT incorporation refined the pore structure, improved interfacial bonding and enhanced crack-bridging capacity, thereby reducing ion penetration and degradation. The mix containing 0.5% CNT exhibited the most favorable performance, indicating it as the optimum dosage for achieving superior mechanical strength and durability. Research limitations/implications The study focuses on laboratory-scale experiments; field validation under real exposure conditions is recommended for further reliability assessment. Practical implications CNT-reinforced concrete can extend the service life of infrastructure in acid- and sulfate-prone environments, reducing maintenance costs and improving sustainability. Social implications Enhancing the durability of critical infrastructure contributes to resource conservation and promotes sustainable construction practices. Originality/value This study presents a novel approach to enhancing concrete durability under chemically aggressive conditions using CNTs. It establishes an optimum CNT content for maximum performance and demonstrates microstructural improvements through SEM, XRD and EDX analysis.