| 摘要 |
PROBLEM TO BE SOLVED: To obtain a cement compsn. which can be used in a slurry state and which gives expanding property to cement, mortar and concrete by incorporating CaO-Al2O3-H2O hydrates, inorg. sulfates and water. SOLUTION: As for CaO-Al2O3-H2O hydrates(CAH), crystalline or amorphous compds. can be used. The crystalline compds. are, for example, CAH10, C2AH8, C3AH6 and C4AH13. The amorphous compds. have 0.5 to 6 molar ratio of CaO/ Al2O3. The crystalline CAH can be synthesized by hydration of calcium aluminate. As for the inorg. sulfates, alkali metal sulfates such as sodium sulfate, or aluminum sulfate, alums and gypsums, can be used, and gypsums, especially gypsum anhydride is preferable. The compounding ratio of CAH and inorg. sulfates is preferably controlled to 30 to 70 pts.wt. of the inorg. sulfates to total 100 pts.wt. of them. |
