Abstract

The proportion of electricity generated by coal-fired thermal power plants has been rising in Japan as a result of the nuclear plant accident caused by the Great East Japan Earthquake of 2011. Coal-fired electricity generation has a large environment impact, so the commercial application of integrated coal gasification combined cycle (IGCC) has been promoted. IGCC is an efficient generating method combining a steam turbine and a gas turbine. However, IGCC plants generate coal gasification molten slag (CGMS) and it is necessary to establish effective utilization methods for this slag for further promotion of IGCC technology. In this paper, the fresh properties, hardened properties and durability of concrete containing CGMS as fine aggregate are investigated. The results show that, in comparison with concrete using conventional fine aggregate, the air content introduced by an air-entraining agent is lower and bleeding is increased when CGMS is used as a fine aggregate. As for the hardened properties, compressive strength is slightly lower, while freeze-thaw resistance is significantly reduced. In additional tests, it is found possible to improve freeze-thaw resistance by increasing the air content