Investigation on thermal deterioration of concreate in severe accident

Abstract

In Fukushima accident on 2011, molten core supposed to be leaked on the concreate floor in containment vessel. Development of small type of core catcher which can be installed in operating nuclear power plant is needed. In this investigation, the thermal deterioration of concreate and Magnesia-Carbon brick observed trough surface observation by microscope and measurement of compressive strength, weight reduction, and difference of void ratio. In addition, permeability measurement for burned concreate was operated. All factor was measured on room temperature situation with enough burned and cooled specimens. As a result, both of concreate and Magnesia-Carbon brick lost its weight, volume, and strength mostly relate with heating temperature. Permeability of concreate also rose as heating temperature rise. Magnesiacarbon brick which heated over 800℃ showed more severe deterioration than concreate heated same situation. Thermal deterioration of both material was observed.