Review of Silica Fume and Metakaolin as Partial Cement Replacements in Fiber-Reinforced Concrete

This review aims to provide a comprehensive analysis of the effects of silica fume and metakaolin as partial replacements for cement in fiber-reinforced concrete (FRC). The use of supplementary cementitious materials (SCMs) has gained significant attention in recent years as a means to enhance the mechanical and durability properties of concrete while reducing its environmental impact. Silica fume and metakaolin are two commonly used SCMs that have shown promising results in various concrete applications. The review begins by discussing the fundamental properties and characteristics of silica fume and metakaolin, including their pozzolanic reactivity and particle size distribution. Subsequently, the influence of incorporating these SCMs on the fresh and hardened properties of FRC is examined. The mechanical properties, such as compressive strength, tensile strength, and flexural strength, are evaluated in light of the varying replacement levels of silica fume and metakaolin. Additionally, the review addresses the durability aspects of FRC with silica fume and metakaolin, focusing on resistance to chloride ion penetration, carbonation, and alkali-silica reaction (ASR). The microstructural changes, hydration characteristics, and pore structure evolution of FRC mixes incorporating these SCMs are also discussed.