| 摘要 |
PROBLEM TO BE SOLVED: To obtain a cement composition mainly used for engineering work and building fields, capable of ensuring retention of slump for a definite time and providing concrete having good initial strengthexpressing property, especially strength expressing property at low temperature. SOLUTION: This cement composition contains portland cement having >=60wt.% 3CaO.SiO2 content, anhydrous gypsum, formic acids, water reducing agent and as necessary, silica fine powder. This castin-place lining comprises driving concrete containing the cement composition, pressurizing and curing the concrete and moving a formwork and joining the concrete. |
