Abstract: A study has been performed on the setting time，compressive strength，drying shrinkage ratio and hydration products of calcium sulfoaluminate ( CSA) cements with different amounts of anhydrite at 5 ℃，20 ℃ and 40 ℃ ． Ｒesults reveal that the effect on the hydration of calcium sulfoaluminate cement clinker depends directly on the curing temperature，although anhydrite can promote the formation of ettringite． At 5℃，anhydrite dramatically delays the early hydration so that the setting time is greatly extended and the early strength is significantly reduced， which is different from the condition at 20 ℃ and 40 ℃ ． Because anhydrite can effectively inhibit the transition from ettringite to monosulfate at high curing temperature，the compressive strength of mortar with CSA cement cured at 40 ℃ is higher than that of CSA clinker．

Key words: calcium sulfoaluminate cement, anhydrite, curing temperature, hydration, hydration products, ettringite, alumina hydroxide