Radiation protective properties of fine-grained concretes and their radiation resistance

Abstract

Abstract Studies have shown that the thickness of the half layer of the gamma radiation flux attenuation with E = 662 keV is 3,5-5,2 cm (depending on the concrete density average) and for a neutron flux with E = 2,5 MeV is 5-6 cm. The radiation resistance of concrete under the influence of gamma radiation large doses, their activity and radionuclide composition after irradiation with neutrons was investigated. To study the behaviour of concrete under the influence of gamma radiation, two series of samples were made. One series was the control, and the second was exposed to gamma radiation. The temperature of the samples during testing did not exceed 40 °C, the dose of gamma radiation was 109 rad. Its value corresponds to the dose that concrete can receive when it comes into contact with highly radioactive wastes from the “Shelter” facility for 300 years. The characteristic of an industrial gamma-ray plant is radiation energy of 1,25 MeV and a dose rate of 2 Mrad/h. Using this setup allows you to reach a dose of 109 rad in less than a month, and 108 rad in 4 - 5 days. Concrete that reached the age of 28 days and stored under normal conditions was exposed to gamma radiation. Analysing the obtained data of physical and mechanical tests of radiation-protective compositions, it can be noted that large doses of gamma radiation practically do not affect the strength of the developed material.