| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a cement additive exhibiting large flowability improving effect and small deterioration of long time strength development when the addition quantity is increased and a cement composition prepared by adding the cement additive. <P>SOLUTION: The cement additive is obtained by pulverizing a fired material containing 2CaO-SiO<SB>2</SB>and 2CaO-Al<SB>2</SB>O<SB>3</SB>-SiO<SB>2</SB>as essential components and contains 10-100 pts.mass in total quantity of 2CaO-Al<SB>2</SB>O<SB>3</SB>-SiO<SB>2</SB>and 4CaO-Al<SB>2</SB>O<SB>3</SB>-Fe<SB>2</SB>O<SB>3</SB>,≤20 pts.mass 3CaO-Al<SB>2</SB>O<SB>3</SB>and 0.01-1.0 pt.mass B<SB>2</SB>O<SB>3</SB>per 100 pts.mass 2CaO-SiO<SB>2</SB>. The cement composition internally contains≤50 mass% cement additive per the cement. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
