LONG TERM HYDRATION PROPERTIES OF SPECIAL CEMENT COMPOSED OF BELITE CEMENT AND LARGE AMOUNT OF POZZOLAN

摘要

Long-term hydration properties of special cement composed of belite cement and large amount of pozzolan was investigated to provide the long-term durability of concrete with the continuous hydration reaction of belite and pozzolan. From the result of this study, following conclusions were obtained. Hydration reaction of belite and pozzolan was continued at more than 3 years, by using coarse belite cement (produced by low-heat Portland cement clinker) and pozzolan, such as fly ash (FA) or coal gasification slag (CGS). Once the Ca(OH)_2 produced at the early hydration process, it is hardly to reduce by following pozzolanic reaction; therefore the hydration reaction of belite cement and pozzolan have to be harmonized. It was also indicated that the hydration reaction of belite is reduced by mixing reactive pozzolan such as fine ground CGS, and the use of FA together with CGS are effective for the harmonizing hydration reaction of belite cement and pozzolan.