Improvement of durability of concrete by granulated blast furnace slag sand

Concrete with granulated blast furnace slag sand has high resistance to freezing and thawing attack without AE agent. However, when rapid hardening portland cement is used, long term curing period is necessary to obtain the effect by granulated blast furnace slag sand. In this paper, it will be shown that ground granulated blast furnace slag and thíckening agent is useful in order to get the effect of granulated blast furnace slag sand at early age. Not only resistance to freezing and thawing attack but also resistance to scaling can be improved by granulated blast furnace slag sand. But, steam curing stunts the improvement of resistance to scaling.