A critical review of iron ore tailings as cement and aggregate substitutes for robust infrastructure: Mechanical, durability, eco-economic, and social impacts

The incorporation of mine tailings in cement mixtures is receiving continuous attention due to the considerable amount being produced during ore processing. Iron ore tailings (IOT) show great potential in this regard. Numerous studies have evaluated their use both as supplementary cementitious material (SCM) and as aggregates. This paper provides a comprehensive overview of the utilisation of IOT in cementitious composites, focusing on the various methods used to activate IOT and examining the durability along with mechanical properties of IOT-based cement mixtures. The findings indicate that while IOT has potential as a cement alternative, its inert crystalline structure requires activation. On the other hand, substituting IOT as fine aggregates enhances mechanical and durability properties. However, to avoid performance degradation, its replacement should be limited to 25%. Additionally, it summarises the environmental, economic, and social viability of using IOT in construction and presents current challenges and future research recommendations. Overall, IOT can be effectively utilised in cementitious composites, particularly as a replacement for natural aggregates, without significant losses.