A study on the mechanical and radiation shielding characteristics of concrete samples reinforced with brass alloy and boron carbide

In this study, the gamma radiation shielding properties of concrete samples reinforced with 10%, 20%, 30%, 40% and 50% of the cement weight of brass alloy were investigated. To test gamma shielding performance of the samples, mass and linear attenuation coefficients, half and tenth value layers, effective atomic number and radiation protection efficiency parameters were determined experimentally, theoretically and Monte Carlo simulations (GEANT4 and FLUKA). The studies were performed at 11 different gamma energies that range from 59.5 to 1332.5 keV emitted from ²²Na, ⁶⁰Co, ¹³³Ba, ¹³⁷Cs and ²⁴¹Am radioactive sources. The obtained results showed that the gamma shielding property of the samples increases with increasing brass alloy amount, and the sample reinforced with 50% brass alloy was the most effective one to shield gamma radiation. Neutron shielding properties of the sample reinforced with 50% brass alloy were therefore investigated by adding 5%, 10%, 15% and 20% boron carbide (B₄C). The neutron permeability, which is an important parameter in terms of the neutron shielding performance of B₄C added concrete samples, was investigated by using GEANT4 and FLUKA simulation programs. While the total macroscopic cross section results obtained with GEANT4 for concretes coded as P0, P50, P50B5, P50B10, P50B15 and P50B20 are 2.0290, 2.0324, 2.0343, 2.0346, 2.0361 and 2.0367 cm-1, respectively, the results obtained with FLUKA are 2.0287, 2.0322, 2.0337, 2.0342, 2.0357 and 2.0362 cm-1, respectively. Therefore, the sample containing 20% B₄C is the sample that best shields neutron radiation. In addition to the radiation shielding properties of the produced samples, the mechanical properties such as compressive strength, Schmidt surface hardness, ultrasound pulse velocity were also tested in terms of usability.