This paper discusses the effect of addition of granulated blast furnac
e slag on the tensile strength of solidified concrete wastes using a h
ydrothermal hot-pressing method, Blast furnace slag of 0-100 mass% was
added to the concrete waste and NaOH solution was used as alkali-acti
vator, Hydrothermal hot-pressing tests were carried out at 250 degrees
C with the water content of 10-30 mass% under the pressure of 20 MPa.
The tensile strength of solidified bodies was determined by Brazilian
test. It was shown that the formation of tobermorite and C-S-H compou
nd improved the strength, The tensile strength reached at 13 MPa under
the following conditions; slag content: 50 mass%, water content: 20 m
ass%, NaOH addition: 1.75 mass%.