- Owing to nuclear technology’s significance in medical, industrial and military applications, this study assessed the effectiveness of some Egyptian raw materials in the production of heavy-weight concrete to shield hazards emitted radiations. Three mix-designs containing different coarser aggregates (dolomite (D), serpentinite (S) and ilmenite (Il)) were prepared. Their workability and physico-mechanical characteristics were examined. The hydrated concretes’ phase composition and microstructure were analyzed using XRD, TGA/DTG and SEM/optical-microscopy. The impact of elevated temperatures (300, 600 and 900◦C for 2 hrs) on the mechanical properties was studied. The volume stability of concrete specimens was investigated using a hot-stage microscope and thermodynamics calculations. Finally, the gamma-ray attenuation was evaluated against the 137Cs radioactive isotope with 0.662 MeV energy. The results revealed that Il-concrete has the highest slump value, highest bulk density and lowest water absorption. Also, it has the mostOwing to nuclear technology’s significance in medical, industrial and military applications, this study assessed the effectiveness of some Egyptian raw materials in the production of heavy-weight concrete to shield hazards emitted radiations. Three mix-designs containing different coarser aggregates (dolomite (D), serpentinite (S) and ilmenite (Il)) were prepared. Their workability and physico-mechanical characteristics were examined. The hydrated concretes’ phase composition and microstructure were analyzed using XRD, TGA/DTG and SEM/optical-microscopy. The impact of elevated temperatures (300, 600 and 900◦C for 2 hrs) on the mechanical properties was studied. The volume stability of concrete specimens was investigated using a hot-stage microscope and thermodynamics calculations. Finally, the gamma-ray attenuation was evaluated against the 137Cs radioactive isotope with 0.662 MeV energy. The results revealed that Il-concrete has the highest slump value, highest bulk density and lowest water absorption. Also, it has the most outstanding efficiency in gamma-ray shielding; its attenuation is higher than D-concrete and S-concrete by 271.2 and 168.1 %, respectively. Replacing dolomite with serpentinite and ilmenite harms mechanical performance. However, the compressive-strength of the prepared concretes is in the range of 24.10–41.06 MPa at 28-days, achieving the building code’s requirements for structural concrete. At elevated temperature, S-concrete showed the highest compressive-strength retention and highest volume stability.…

