2019 Volume 73 Issue 1 Pages 103-110
The use of blast furnace cement is being promoted to reduce CO2 emissions during cement production, but in cold climates such as Hokkaido region there is a concern that initial strength of blast furnace cement may decrease by using air entrained agent (AE) for improving freeze-thaw resistance and scaling may occur. However, increase with air content decrease compressive strength, although it is possible to take measures by mixing a novel accelerator using a combination of a polyol and a sulfate and a new frost damage inhibitor for concrete such as oil type as a new method that is independent of air content, it has not been investigated whether the combined use of these agents suppresses the development of initial strength. Moreover, the effect of combined use of accelerator and a frost damage inhibitor on the reaction of blast furnace slag is not clear. Therefore, in this research, we clarified the mechanism of the strength development of the hardened blast furnace slag cement using the frost damage inhibitor and the accelerator together by performing a strength test and phase composition analysis by XRD Rietveld method and SEM observation. As a result, it was found that the C3S and C3A reaction rate increased by the accelerator, and the frost damage inhibitor did not inhibit the reaction.