Design of masonry mortars fabricated concurrently with different steel slag aggregates

• The simultaneous application of different slag in mortar as fines is presented.
• The mixtures reached are suitable to produce masonry materials with a standard strength.
• Properties of the mortar change in accordance with the degree of substitution of sand by steel fines.
• Microstructural characterisation show good distribution between all of its components.

The simultaneous application of electric arc furnace slag and ladle furnace white slag, in substitution of natural fine aggregate in masonry mortars, is presented with the principal objective of achieving mixes that show a similar performance to conventional mortars. Materials dosed with steel slag fines at different levels of substitution (25%, 50%, 75% and 100%) were designed, employing commercial admixtures in the samples. A comparative study of the most significant mortar properties is conducted, such as workability, adhesiveness, water retentivity and mechanical strength, between the mortars prepared with natural fine aggregate and those manufactured with additions of slag. The results indicate that technically viable mortars may be obtained for their use in construction and building, which thereby achieve the reuse and valorization of waste products that would otherwise be disposed of in landfill sites.