Low-Activation Reinforced Concrete Design Methodology (LARCX6) — Development of Low-Activation Cement —

摘要

When nuclear plants will reach to decommission stage, a huge amount of concrete should be disposed as radioactive waste. To reduce the amount of radioactive concrete, the most effective methodology is not to use the materials of high radionuclide content: for example, using limestone aggregate. However, concrete uses Portland cement for hardening, therefore, it is difficult to reduce the amount of radioactive concrete unless radionuclide content in cement is reduced. So in this study, we tried to develop the new type of Low-activation cement by reducing of radionuclide as europium and cobalt. As a result, we could reduce the amount of europium and cobalt in cement significantly, and obtained the result that the new cements can reduce radioactivity to one-third or less against commercially Portland cement in Japan.