| 摘要 |
A cementitious composition which, when mixed with water, is capable of setting rapidly into a hard mass of high compressive strength without substantial shrinkage during setting, and having reduced wet and dry volume changes in the hardened state comprises aluminous cement, gypsum, a drying shrinkage inhibitor and a wet expansion inhibitor. The wet expansion inhibitor is a lithium salt which may be added in an effective amount ranging between 0.01 to 0.5 percent, by weight, based on the aluminous cement and gypsum and preferably between 0.1 and 0.3 percent. It is preferred to employ between 60 and 90 percent, by weight, aluminous cement and between 10 and 40 percent, by weight, gypsum. The hardened drying shrinkage inhibitor, preferably Portland cement, is added in an amount ranging between 0.1 and 25 percent, by weight, based on the aluminous cement and gypsum, and preferably between 1 and 20 percent. |
