Recent development in the application of ultra-fine cement and par-used in Japan, ultra-fine cement and the lithium siliticle-size distribution-controlled cement are described, focusing on cate-based repairing material are used for their proper the Japanese experience. They are modified by mixing other fine applications according to their special features. blending components, organic materials, and admixtures. Their
An ultra-fine binder is used as the hardening mateuses are diversified not only in soil and rock grouting, and filling rial to improve peat deposits soil contairting much waand sealing of crack in concrete, but also in peat soil hardening, ter stretching over a cold district. The hardening mamaterials of cement for high performance concrete, and adhesives for terial for peat deposits is a binder composed of fine bonding insulators with metal fillings. ADVANCED CEMENT cement and ultra-fine slag and gypsum. The physical BASED MATERIALS 1994, 1, 150--154 properties of the hardening material are controlled by KEY WORDS: Composite, Crack injection, Grout, Harden-changing the mixing ratio and fineness according to a ing, Repair, Surface modification, Ultra-fine cement, Viscos-geologic formation of peat soil. ity Development of cement for high performance concrete with high fluidity and strength is also being investigated by finely grinding slag, fly ash, and limestone as well as cement itself and controlling their par-~he cementitious binder has been grouted so ticle-size distribution by classification. far for reinforcing the foundation rock and Besides this, particle-size distribution-controlled stopping the leakage of water from it in the fine cement is used as the bonding material of insulators with metal fittings in the power-transition line. building of a tunnel and the construction of a dam, a high-rise building, and a subsurface structure in Japan. Grouting materials are roughly classified the water glass-and organic resin-based solution types and the