Admixture for cement composition with high coal ash powder content, and cement composition and spray material with high coal ash powder content containing the same

摘要

PPROBLEM TO BE SOLVED: To provide a cement composition highly containing a coal ash powder and having an initial strength equivalent to or higher than that of a cement composition not containing a coal ash powder. PSOLUTION: An admixture used for the cement composition highly containing a coal ash powder contains plaster and an ettringite-based quick-hardening agent in a molar ratio SOSB3/SB/AlSB2/SBOSB3/SBof SOSB3/SBin the plaster to AlSB2/SBOSB3/SBin the ettringite-based quick-hardening agent of 1.5 or higher. The cement composition contains the admixture, and a spraying material containing the composition is also provided. PCOPYRIGHT: (C)2008,JPO&INPIT