Design of protective solutions based on a nanomodified gypsum alumina cement system and investigation of their properties

The object of this study is the structuring processes and the physical-mechanical properties of nanomodified ion-protective coatings based on the gypsum-alumina cement system. Under the influence of ionizing radiation, defects are formed in the calcium hydroxide crystalline lattice causing radiation shrinkage. As a result of the shape anisotropy and aggregate deformations, uneven deformations are transferred to the concrete skeleton. Therefore, the effective use of gypsum alumina binders for creating ion-protective coatings for biological shielding against radioactive radiation is a pressing issue being solved. The sulfate and sulfoaluminate phases solution modification by carbon nanotubes (CNTs) leads to a decrease in the linear expansion coefficient and an increase in the gamma-ray scattering coefficient by 30–40 % due to the high specific surface area. The results are explained by the ettringite phase formation leading to the 15 % increase in the chemically bound moisture content in the optimal composition. At the same time, arithmetic mean value of the chemically bound moisture content improves the linear attenuation coefficient of ionizing radiation by 0.0088–0.009 cm–1. Under such conditions, the total coefficient could reach up to 0.354 cm–1 making it possible to reduce the radiation-protective layer equivalent thickness (14.6 cm–1) by 1–1.5 mm. A special feature of the result, which made it possible to reach the purpose of the study, is the maximum 46 % ettringite content in the most complete water binding contributing to the effective ionizing radiation absorption in the protective coating. The application of research findings is solutions for ion-shielding coatings for X-ray rooms