EAF slag in asphalt mixes: A brief review of its possible re-use

- EAF slag has excellent properties for use as coarse aggregate in high proportions.
- Some economical drawbacks are increased bitumen absorption and heavier mixtures.
- The mechanical behavior of slag mixes is generally better and their skid resistance is excellent.
- The use of EAF slag as fines appears to worsen the water sensitivity of the mixes.
- There are no problems in the swelling or leaching tests on bituminous mixtures.

Electric arc furnace (EAF) slag has excellent mechanical properties that justify its use as aggregate in the manufacture of bituminous mixes. Its main properties, the problems with its application, and the important features of the mixtures made with this slag (mechanical behavior, resistance to fatigue and permanent deformation, moisture susceptibility, skid resistance, permeability, noise absorption, etc.) are all analyzed in this review. It is concluded that the use of EAF slag is mainly recommended in partial replacement of the coarse aggregate, in all types of bituminous mixtures, following appropriate pre-treatment. This use of the EAF slag improves the mechanical performance and durability of the mixes, as well as their long-term sustainability.