Contamination behaviour on the surface of building materials

Abstract

Study of radionuclides penetration into building materials is connected with many difficulties of methodical character: difficult micro- and macro relief of the materials surface, rate of their weathering or growth on their surface of biogenic forms, a considerable variety of physical and mechanical properties of like building material. White and red bricks are considered to be the most spread building materials. Slate and tile were used as materials for roofs. Contaminated surface layer of building material samples was studied with three ways supplemented each other: 1) removing of building material layer by polishing-out; 2) measuring of activity of polished-out material layer after each treatment and simultaneously determining of a removed layer mass; 3) autoradiographical researches of radionuclide distribution on different cross-sections of building material samples. The biggest gradient of radionuclides concentration is observed in the layer of 70-80 g/m2 mass. The coefficient of decontamination in this case is made up 1.5-1.6. The further removing of deeper layers gives lower effect of decontamination because a considerable amount of radionuclides is distributed in deeper layers of building materials. The most considerable changes of roughness when tile processing were observed after the first surface treatment. An average value of a removed layer were made up about 80 µm.