Study on Environmental and Mechanical Properties of Irradiated Concrete

The radiation dose to the biological shield concrete of the JPDR(Japan Power Demonstration Reactor; where electric power had actually been generated for some years, was evaluated and the radiation effect on the compressive strength of the concrete was investigated. The data obtained can be used a fundamental information for predicting the life time of a large commercial nuclear power plant. The major results of this study are summarized below. a) The maximum dose of the fast neutron and -f-ray at the inner surface of the biological shield concrete are 1.11×10^<18>n/cm^2 and 4.77×10^<18> Gy, respectively, at the level of the reactor core, The generation of heat within the shiled concrete is similar to that of the distribution of the γ-ray flux. b) The maximum fast neutron dose irradiated to the concrete samples used for the measurements was 1.11×10^<18>n/cm^2, which is almost the same level as that at commercial nuclear power plants. The compressive strength of the concrete samples increased with the fast neutron fluence, which depended on the distance from reactor core level.