Valorization of solid wastes in concrete production: an overview of materials, properties, mechanisms, and emerging technologies toward upcycling

Valorizing solid wastes in concrete production has the potential to deliver three-fold benefits of minimizing landfill, reducing material costs, and improving concrete properties, therefore adding value to both economic development and environmental management. Despite such significant potential, the practical utilization of solid wastes in concrete has been limited due to various factors. This paper overviews solid wastes utilized in concrete production, aiming to clarify the capabilities and limitations through surveying solid wastes that serve as alternative raw materials of concrete, underlying mechanisms, concrete properties, and emerging technologies toward upcycling. The types of wastes reviewed include industrial, agricultural, municipal, and construction streams, which play roles as binders, aggregates, or fillers, impacting the fresh, mechanical, durability, and multifunctional properties of concrete. The underlying physical and chemical mechanisms that govern concrete properties are discussed. Advancements in nanotechnology, carbon sequestration, artificial intelligence, and advanced manufacturing are examined as emerging techniques. Key challenges and new opportunities are discussed to provide a roadmap for future research and development of green concrete technologies.