| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a quick-hardening cement admixture for low temperature, which is mixed and kneaded into a cement composition to impart excellent potlife, i.e. 60 min or longer, a compressive strength of 5 N/mm<SP POS="POST">2</SP>or higher at a material age of 3 hr and a compressive strength of 30 N/mm<SP POS="POST">2</SP>or higher at a material age of 24 hr, even when the material temperature of the mixed cement composition and the environmental temperature are 5°C, and to provide a quick-hardening cement composition for low temperature, which is excellent in potlife, i.e. 60 min or longer, has a compressive strength of 5 N/mm<SP POS="POST">2</SP>or higher at a material age of 3 hr and has a compressive strength of 30 N/mm<SP POS="POST">2</SP>or higher at a material age of 24 hr, even when the material temperature and the environmental temperature are 5°C. <P>SOLUTION: The quick-hardening cement admixture for low temperature comprises calcium aluminates with a prescribed percentage of glass content, gypsum, alkali metal sulfate, alkali metal carbonate and a setting retarder. Preferably, the calcium aluminates comprise crystalline calcium aluminates and amorphous calcium aluminates. <P>COPYRIGHT: (C)2012,JPO&INPIT</p> |
