| 摘要 |
PROBLEM TO BE SOLVED: To provide a cement admixture excellent in expansion performance and also to provide a cement composition containing the cement admixture. SOLUTION: This cement admixture is obtained by subjecting a CaO raw material, an MgO raw material, an Al2O3 raw material, an Fe2O3 raw material and a CaSO4 raw material together to heat treatment and contains free lime, free magnesia, calcium aluminoferrite and anhydrous gypsum, wherein the free lime content is 30-65% and the free magnesia content is 1-10%. This cement composition contains cement and the cement admixture. |
