A Summary of Research Results on Radiation-Induced Deterioration of Concrete Commissioned by Nuclear Regulatory Authority

Abstract

This contribution is a summary of a research project results on radiation-induced deterioration of concrete commissioned by the Japanese Nuclear Regulation Authority (NRA). Neutron irradiation can cause expansion of the minerals in aggregates. This expansion is highly dependent on the mineral type, but is especially large for quartz. When aggregate with a high amount of quartz, which expands due to amorphization by neutron irradiation, is used in concrete, the deterioration of the concrete is significant. Other results showed that the effects of gamma radiation on concrete and concrete components were almost comparable to those after heating and drying. As for the heat and drying effects on concrete, it was found that the strength of concrete is determined by the strength change due to the colloidal nature of cement paste and the cracking around the aggregate caused by the difference in volume change between the aggregate and the paste after drying.