Effect of Mineral Admixtures and Curing Regimes on Properties of Self-Compacting Concrete

Abstract

This study investigated the influence of mineral admixtures (fly ash, silica fume, metakaolin) and curing conditions (water immersion, polyethylene glycol, gunny bags, accelerated curing) on the properties of self-compacting concrete (SCC). The rheological properties, compressive strength, chloride penetration resistance, and microstructure were evaluated. Incorporating mineral admixtures improved the workability, strength (up to 53% increase), and durability of SCC compared to plain mixes, with 20% metakaolin replacement optimal. Water immersion curing enhanced the compressive strength (3–15% increase) and chloride resistance (up to 30% decrease in migration coefficient) owing to improved hydration and microstructural refinement. Mineral admixtures reduced the sensitivity of SCC to the curing method. Microstructural analysis showed higher density and additional C-S-H phases with mineral admixtures under wet curing. The study demonstrates that optimized SCC containing appropriate supplementary cementitious materials and proper external curing can achieve high performance.

Keywords

• compressive strength
• curing conditions
• metakaolin
• scanning electron microscope
• self-compacting concrete