Recycling of scale and steel chips waste as a partial replacement of sand in concrete

Modification of concrete properties by the addition of appropriate materials is a popular field of concrete research. This study is focusing on the use of selected waste of iron and steel industry (steel chips and scale) as a partial replacement for sand in the production of concrete. In this research study, concretes were made with steel chips scale (ScC) and (SchC) as substitution for raw sand. Sand was replaced by these waste in different proportions (25%, 50%, 75%, and 100%) by weight of sand. The aim of this study is to investigate the compressive strength and absorption properties for gamma radiation of concrete with steel chips and scale waste as a partial replacement for sand. The tests results obtained from concretes produced with scale and steel chips were compared with those in conventional concrete (CC-0). The experimental results indicate that, the addition of these waste to concrete enhances the absorption of gamma radiation without impairing other technical features of the investigated concrete. The data shows, that the concrete mixed with steel chips have better strength than conventional concrete, while in the case of concrete mixed with scale in excess of 25%, the strength become deteriorated. The linear attenuation coefficient of gamma radiation of concrete with a mixture of scale and steel chips with 75% and 100% was very good while the rest have good and satisfying radiation properties. Consequently, concrete prepared from the iron and steel industry solid waste containing steel chips and scale could be preferred for buildings as shielding concretes against gamma radiation. In this research the thickness of the concrete shield which can be used instead of the conventional concrete was also calculated. (C) 2011 Elsevier Ltd. All rights reserved.