Application of Graphite Tailings in Concrete Manufacturing: A Review

Large-scale mining of graphite, a crucial strategic mineral, generates substantial amounts of graphite tailings (GT). The stockpiling of this solid waste occupies vast land resources and poses persistent environmental risks due to potential heavy metal leaching. Repurposing GT into construction materials presents a promising solution, with its use as a partial replacement for fine aggregates in cementitious composites being one of the most effective methods. This review systematically consolidates current research on graphite tailings cement mortar (GTCM) and graphite tailings concrete (GTC). Due to its physicochemical properties comparable to natural sand, GT is suitable for producing building materials. Studies consistently demonstrate that a substitution level of 10% to 20% optimizes overall performance. This optimal range enhances particle packing, promotes cement hydration via pozzolanic activity, and refines the microstructure, leading to improved workability, superior mechanical strength, and enhanced durability, including resistance to permeability, freeze-thaw cycles, and chemical attacks. Moreover, the inherent carbon content imparts electrical conductivity to GTC, enabling functional applications like de-icing and structural health monitoring. The successful utilization of GT also extends to lightweight foamed and autoclaved aerated concrete. However, research on the structural behavior of GTC components remains limited. Preliminary findings on beams and columns are encouraging, but comprehensive studies on their seismic performance and design methodologies are urgently needed to facilitate the widespread engineering application of this sustainable material and mitigate the environmental impact of tailings accumulation.