Can Steel Slag Be Used as an Aggregate in Concrete and How? A Technical Approach by and Testing and Theoretical Molding

Steel slag is the molten byproduct from steelmaking operations that is subsequently air-cooled for use. It has been used in cement manufacture and as unbound granular materials in construction. While numerous studies have revealed that concrete containing steel slag aggregate possesses good mechanical properties, and slag, as a byproduct, is cheaper than virgin aggregates, its practical use in Portland cement concrete is currently a forbidden area in the construction practices. What is the practicality, where is the crux of converting research results into to real production, and how to build the bridge between the laboratory experiment and the end products? Based on the philosophy of slag utilization, i.e., laboratory testing, field demonstration, and criteria establishment, the questions to be answered includes (1) two distinct laboratory test methods to determine the expansion force generated by slag particles; (2) conversion of the expansion force of mass slag aggregate to the expansion force of single slag particle; (3) mechanical disruption model of slag failure; and (4) usability criteria for the use of steel slag in a rigid or restrained matrices. The paper introduced the answers for the first two questions; and provides the mechanical model and criterion deduction to answer the other two questions that lead to criteria and specification establishment.