A comprehensive review on all-solid-waste cementitious materials: activation, preparation, sustainable performance...

Solid waste represents a misplaced resource whose comprehensive utilization remains a global priority for achieving carbon neutrality in construction. The development of all-solid-waste cementitious materials (ASWs) mitigates the environmental challenges associated with bulk waste accumulation while effectively reducing CO₂ emissions in the construction sector. This paper systematically reviews industrial solid waste-based cementitious materials (ISWCs) as sustainable alternatives to Portland cement (PC). It elucidates the physicochemical characteristics and multi-scale activation strategies for typical precursors such as fly ash (FA), slag (SS), and coal gangue (CG). A central focus is placed on the synergistic design of multi-source wastes, analyzing the correlation between gel-matrix evolution and macroscopic properties. The review evaluates the integration of machine learning and ternary phase diagrams for intelligent mix optimization and performance prediction. Furthermore, the sustainability of ISWCs is critically assessed regarding carbon footprints, durability, life-cycle economic benefit, and leaching safety. The engineering potential of these materials in building materials, road infrastructure, mine backfilling, soil stabilization, coating materials, and 3D concrete printing is evaluated, alongside an analysis of technical, economic, and policy barriers to large-scale adoption and corresponding measures to facilitate broader application. This work provides a rigorous reference for the standardization and large-scale deployment of green, functionalized cementitious materials in complex environments.