CEMENT ADMIXTURE, CEMENT COMPOSITION, QUICK HARDENING GROUT MATERIAL, QUICK HARDENING GROUT, AND METHOD FOR PREVENTING DEFORMATION OF NATURAL GROUND USING THE SAME

摘要

PPROBLEM TO BE SOLVED: To provide a cement admixture, a cement composition, a quick hardening grout material, and a quick hardening grout which are characterized in that there is non bleeding and no material separation, flowability is not lowered largely, pot life is secured at least 30 min, strength can be developed in a short time without shrinkage, and the elution of hexavalent chromium from a hardened body is very low; and to provide a method for preventing deformation of natural ground using the same. PSOLUTION: The cement admixture contains a calcium aluminate compound, gypsums, a blast furnace slowly cooled slag powder, and an expansive material. The content of sulfur existing as non-sulfuric acid sulfur in the blast furnace slowly cooled slag powder is set to be 0.5%. Further, the cement admixture has a vitrification rate of 30 %. The cement composition contains cement, the cement admixture and a setting modifier. The quick hardening grout material contains fine aggregate and the cement composition. The method for preventing deformation of natural ground comprises using the quick hardening grout. PCOPYRIGHT: (C)2006,JPO&NCIPI