Metal-Nails Waste and Steel Slag Aggregate as Alternative and Eco-Friendly Radiation Shielding Composites

Abstract

Metal waste recycling has become a global requirement owing to its environmental benefits and powerful economic activity. Metal nail waste (MNW) is a byproduct of metal nail manufacture. MNW has an equal size, contains a high ratio of iron, and has a high specific gravity comparable to normal aggregate. We present MNW recycling as a partial replacement for fine aggregates and electric arc furnace steel slag (EAFSS) as coarse aggregates to produce sustainable heavyweight concrete (HWC). Our main research aim was to study the radiation shielding and mechanical properties of sustainable HWC by partially replacing MNW with 10, 20, 30, and 40% sand. EAFSS is a coarse aggregate for 60% of the total volume. Fresh and hardened properties of HWC are presented. Furthermore, we analysed the internal structure of HWC mixes using a scanning electron microscope. Our results showed the positive effects of MNW on the unit weight of concrete. The density of HWC mixes ranges between 2650 and 3170 kg/m3. In addition, MNW contributes to increasing the compressive strength of concrete mixes with their use of up to 30%. Therefore, the MNW ratios improved the failure behaviour of HWC mixes. The improved linear attenuation coefficient of HWC mixes was due to using MNW ratios and higher densities than the reference mix.