Value added usage of granular steel slag and milled glass in concrete production

Abstract

Industrial development has generated enormous conveniences for humans at the cost of environmental pollution. Cement production is a major cause of carbon dioxide emission in the construction industry and utilization of a large number of aggregates in concrete is causing scarcity of natural resources and irreversible depletion. The practice of utilizing industrial wastes in the production of concrete can be a useful solution. In this research, the green concrete of enhanced properties is produced by incorporation of milled glass as partial replacement of cement and fine aggregates are replaced by granular steel slag with different dosages. Ten types of concrete mixes substituting cement by glass powder (10%, 20% and 30%) and sand by granular steel slag (40%, 60% and 80%) were assessed in terms of rheological, mechanical and microstructural properties. Results indicated that concrete having 80% granular steel slag and 20% glass powder shows maximum increase of 42%, 16%, 16% and 14% in splitting tensile strength, flexural strength, modulus of elasticity and compressive strength respectively. Scanning electron microscopy depicts the formation of secondary calcium silicate hydrate (CSH) and improved packing density in concrete mixes having granular steel slag and glass powder. Thus, granular steel slag and glass powder can effectively be used as cement and sand replacement in the production of value-added green economical concrete and reducing environmental pollution.