Neutron activation analysis for determination of induced radioactivity in concrete of nuclear reactor shielding

The content of binding agent components and aggregates of shielding concrete was studied to identify nuclides contributing to the long-lived radioactivity of concretes used in nuclear reactor shielding. Elemental content was determined by neutron activation analysis. It is shown that the nuclides mainly responsible for the long-lived activity are 152Eu, 154Eu, 60Co and 134Cs. Based upon the experimental data obtained, calculations of the specific activity of concrete ingredients were performed and diagrams of the dependence of the specific activity versus time are presented. (author) 11 refs.; 2 figs.; 3 tabs