Abstract:Using blast furnace slag as cement substitute material to prepare novel cementing material is an important direction of comprehensive utilization of resources, it can achieve its cementitiousSbehaviorSpotential more quickly with the help of alkali activator, one important factor to restrict the practical application of production is the alkali activator. NaOH is a widely used alkali activator in laboratory but bring some dangerous to the application and accelerate the instrument loss due to its highly corrosive. Using gypsum as an addictive and CaO as the alkali activator to explore the possibility of prepare the novel cementing material. The best preparation parameters of CaO, cementing material/tailings ratio, gypsum were concluded through orthogonal test. Under the optimal parameter (CaO=10%,cementing material/tailing ratio=1:4, gypsum =5%), the 28 d compressive strength of cement filling material was 5.67MPa, which meets the requirements of backfilling.