Effect of Serpentine Aggregates on the Shielding, Mechanical, and Durability Properties of Heavyweight Concrete

Concrete is a material that can easily absorb nuclear radiation, and in this process, the density of concrete is an essential factor in absorbing the rays. Therefore, due to performance limitations and thickness, heavyweight concrete is used. In this study, serpentine coarse aggregates (SCAg) and serpentine fine aggregates (SFAg) were used as a substitute for sand and gravel in heavyweight concrete containing lead slag to protect against gamma rays. Determination of mechanical properties (compressive strength, tensile strength, and ultrasonic pulse velocity), physical properties (water absorption and electrical resistivity), and shielding properties (shielding against gamma rays) were among the main objectives. The results indicated the positive effect of SFAg and SCAg on the shielding properties of concretes against gamma rays. The replacement of SFAg and SCAg with natural aggregates increased the density of the samples, which resulted in an increase in 3.8 to 42.9% in the linear attenuation coefficient against gamma rays. SFAg has a significant effect on gamma-ray attenuation, especially when these materials are made of high-density minerals, due to their property of reducing the pores in concrete.