<p>Replacing cement with steel additives (waste materials or steel ore (iron oxide)) contributes to the sustainable production of concrete, improving its mechanical and radiation-shielding properties. Consequently, an experimental investigation was undertaken to examine the effects of using waste steel additives — such as brake lining, rolling mill scales, iron filings, and steel ore (hematite) — on the properties of sustainable concrete containing slag as a coarse aggregate. The effect of varying ratios of steel additives on the physical, mechanical, and gamma radiation shielding properties of sustainable concrete was examined. Gamma-attenuation measurements were taken with these mixtures at three gamma energies: 0.66, 1.17, and 1.33 MeV. The experimental results showed that using brake lining, rolling mill scales, iron filling, and hematite improved the physical, mechanical, and radiation properties of concrete. SEM analysis indicates microstructural improvement with waste steel. It was observed that the linear attenuation coefficient lies between 0.0923 cm^-1 and 0.2532 cm^-1. The study concluded that adding steel additives to the concrete mixture delivered superior performance, provided a solution for waste disposal, and promoted environmental sustainability.</p>