Evaluation of EAF Slag as a Sustainable Aggregate in Counterweight Concrete within the Scope of Green Transformation

Electric arc furnace (EAF) slag has strong potential as a sustainable high-density aggregate, yet it remains underutilized in current industrial practice. In this study, EAF slag was used as the main aggregate in counterweight concretes for white-goods applications. Five low-cement mixtures were developed by reducing Portland cement content from 14% to 6% while increasing EAF slag content from 84.5% to 92.5%. The prepared mixtures were cast, cured for 2, 7, and 28 days, and evaluated through apparent density, water absorption, porosity, compressive strength, visual inspection, and ultrasonic pulse velocity testing. All formulations exceeded the 44 MPa 28-day compressive strength target. The optimized R5 mixture, containing only 6% Portland cement and 92.5% EAF slag, achieved 80.89 MPa at 28 days with an apparent density of 2.93 g/cm³. The results confirm that EAF slag can be used to produce high-density, high-strength counterweight concrete while supporting slag valorization and lower cement use.