Properties of concrete with processed granulated blast-furnace slag as fine aggregate Available to Purchase

Exploring the use of non-organic solid wastes from mines and mineral industries, such as metallurgical slags, and tailings as a replacement to natural sand in concrete can provide sustainable options to save the natural river sand reserves. River sand for construction is environmentally and economically unviable in several countries of the world. The present investigation intends to explore the suitability of unused granulated blast-furnace slag (GBS) stocks as fine aggregate in concrete. The GBS was processed using a vertical shaft impactor to modify the shape parameters of the granules. The processed GBS (PGBS) content in concrete was varied between 0 and 100%, and the mechanical and microstructural properties of concrete were characterised. The workability of fresh concrete, compressive strength, tensile strength, stress–strain characteristics, drying shrinkage and development of bond between concrete and reinforcement were investigated. The results show a considerable increase (∼40%) in the long-term strength of concrete with 100% PGBS. The PGBS-based concrete showed higher compressive strength than the strength of the reference concrete. Using X-ray diffraction and thermogravimetric analysis techniques, the hydration products present in the PGBS and river sand-based concrete were qualitatively and quantitatively assessed.