Two of the major goals of sustainable development in transportation infrastructure are to reduce energy consumption and conserve natural resources. The production of asphalt mixtures involves consuming high amounts of energy and nonrenewable natural resources. This study investigated the use of Electric Arc Furnace Slag (EAFS) as a substitute for coarse aggregates in Warm Mix Asphalt (WMA) mixtures. In the test specimens, 0, 25, 50, and 75% of natural coarse limestone (retained on 4.75mm sieve) were replaced with EAFS. WMA specimens were also modified with Sasobit at a concentration of 1.5% by weight of bitumen. After testing the aggregates and EAFS, the Marshall method was used to determine the Optimum Bitumen Content (OBC) for 8 series of HMA and WMA mixtures. Because of the high porosity of EAFS particles, the mixtures containing this material showed a higher than normal OBC. To study their mechanical properties, the specimens were subjected to the Indirect Tensile Strength (ITS) test, resilient modulus test (at 25°C and 40°C) and dynamic creep test at 40°C. The results showed that because of the increased mixture stiffness in the presence of Sasobit and better interlocking of EAFS particles compared to limestone aggregates, the use of these materials improves the mechanical properties of WMA and HMA mixtures. The mechanical properties of the mixtures improved differently by the characteristics of the experiments and the type of loading. The most distinguished improvement was observed in the dynamic creep test (up to 343%) and the slightest improvement was observed in the ITS test (up to 17%).

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