Abstract

Ground granulated blast furnace slag (GGBFS) and copper slag (CS) are industrial waste by-products, which are mostly discarded in landfills. Alternatively, they can be used in concrete production to reduce the consumption of cement and natural aggregates. One of the applications that can benefit from heavy-weight aggregates such as CS, is concrete tailored for radiation shielding purposes. However, there was no prior study on effect of combined use of CS and GGBFS on radiation shielding capability of concrete. This study is aimed to address the effect of GGBFS and CS content on gamma-ray shielding and mechanical performance of high-density concrete. For this purpose, concrete mixes were prepared with different percentages of GGBFS (0-60) and CS (0-100) as a partial replacement of cement and natural fine aggregate, respectively. The workability, compressive strength, splitting tensile strength, and radiation shielding capability of concrete mixes subjected to Cs-137 and Co-60 point sources were evaluated. Based on the test results, the workability of fresh concrete was enhanced (up to 63) with increasing replacement ratios of GGBFS and CS. The optimum compressive and splitting tensile strengths were obtained by incorporating 30 GGBFS and 50 CS, which were about 20 higher than that of the control mix. The linear attenuation coefficient increased slightly with GGBFS content. On the other hand, the use of heavyweight CS aggregates increased the linear attenuation coefficient by up to 31. Results showed that concrete made with 60 GGBFS and 100 CS exhibit superior radiation shielding capability and satisfies the strength requirements for structural applications. Therefore, it is suitable for radiation shielding of structures such as healthcare centers. Finally, the ecological analysis revealed that the concrete made with recycled materials is Eco-friendlier and contributes to sustainable development of construction industry.