| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide blast furnace slag cement which hardly expands due to a sulfate, in order to solve the following problem: concrete produced from blast furnace slag cement being a mixture of high alumina blast furnace slag fine powder with portland cement expands due to the generation of ettringite when the concrete is in contact for a long period of time with soil in which sulfate remains, resulting in the destruction of the concrete structure. <P>SOLUTION: In mixed cement mainly containing blast furnace slag fine powder wherein the ratio of alumina is 12-17.5 mass% and portland cement, the mixing ratio of the blast furnace slag fine powder is controlled to 10-60 mass%, and the mixed cement is mixed with gypsum having a specific surface area of ≥7,000 cm<SP POS="POST">2</SP>/g, wherein the mixing ratio is 2-4 mass% expressed in terms of SO<SB POS="POST">3</SB>. The mixed cement is used as a raw material of sulfate-resisting concrete. <P>COPYRIGHT: (C)2012,JPO&INPIT |
