Abstract
This paper deals with how to use a large amount of powdered industrial by-products, such as ashes from the iron casting process and reducing slag from the electric furnace, for concrete. The key in this study lies in how to reduce water content in concrete for getting proper mixing capability. The second point is how to control flash setting and expansion of concrete caused by reducing slag. The addition of proper amount of sodium chloride and gypsum in concrete can solve the problems and the application of the concrete to armour unit was done successfully in the field of sea. In addition, it is confirmed that the reducing slag can prevent hexavalent chromium dissolving out from concrete.
