Hydration behavior and related physical properties of cement at lower temperatures (2～8℃) with natural gypsum replaced by calcined gypsum and calcined alunite were studied,and XRD,DTA and SEM measurement analyses were conducted.

Experiment results show tha t the slag motar blending strength reaches higher value than ordinary portland c ement (OPC) with alike level when it is activated by lime, lime hydrate,lime hyd rate+calcined gypsum or ,lime hydrate+calcin ed gypsum+clinker; its compressive strength is up to P ·O22.

The influences of adding calcined gypsum instead of dihydrate gypsum and adding a little limestone on the physical properties of cement were investigated.