Eco-friendly warm mix asphalt mixtures incorporating electric arc furnace steel slag as substitute to conventional aggregates

The use of steel slag in the creation of warm mix asphalt (WMA) mixtures has been established in the current study as an environmentally friendly approach to generating the asphalt mixtures used in pavement engineering. This article assesses the influence of WMA additives (Sasobit and Zycotherm) on performance properties of asphalt mixtures produced with electric arc furnace (EAF) steel slag as a substitute for conventional aggregates. Conventional (penetration, softening point, and ductility), viscosity, and Fourier-transformed infrared spectroscopy (FTIR) tests were performed to investigate the influence of WMA additives on asphalt binder. Subsequently, Marshall mix design, wheel tracking, indirect tensile strength, Marshall stability ratio, and ultrasonic pulse velocity tests were performed on asphalt mixtures. The laboratory tests on asphalt binders indicate that addition of WMA additives to asphalt binders increases pumping ability due to high viscosity and increase resistance to moisture damage based on FTIR results. Findings of asphalt mixtures show that mixtures made with EAF steel slag had greater moisture resistance and rut resistance than combinations made with conventional aggregates. In addition, Sasobit outperformed other WMA additives in terms of rutting resistance and moisture damage qualities, regardless of the kind of aggregate.