Evaluating potential expansion and strength of compacted steel slag aggregates at different compaction density

Steel slag aggregates can be utilized as unbound materials for road bases or as fine/coarse aggregates in asphalt/cement paving concrete. However, the availability of free lime (f-CaO) in the materials is detrimental to volumetric stability, affecting the strength or durability of resulting paving products incorporating steel slag aggregates. This paper investigates the potential expansion of fine and coarse steel slag aggregates compacted at different compaction densities. The experimental results exhibited a higher stability of the coarse granular mixture exposed to water than the fine one. Also, more compaction increased expansibility in the fine mix, especially at high compaction density. Furthermore, the graded steel slag aggregate exhibited higher strength than the other aggregates. The findings provide reference information on the useability of steel slag in cement-based materials, like the replacement of coarse aggregate is better than the fine ones in volume stability of steel slag concrete.