Aiming at flue gas desulphurization gypsum(FGD) and fly ash(FA), which are two kinds of industrial wastes discharged from the power plant, the active composite mineral admixture used in the concrete was developed and studied. FGD and FA were mixed with appropriate proportion and added into the cement mortar to replace the equivalent cement. Based on some methods of active excitation, the optimal proportion of FGD and FA was researched by controlling the mortar fluidity, the early strength and the strength development law. And the action effect of FGD-FA active mineral admixture, which in the microstructure of cement based material, was researched and evaluated by Scanning Electron Microscope (SEM) experiment. The results showed that FGD and FA are mixed with the ratio of 1∶2, and added into the cement mortar to replace the 30% equivalent cement, then the FGD-FA cement mortar exhibit the good mortar fluidity and the early strength, the later strength can catch and even exceed that of the reference cement mortar. The results of SEM indicated that the activity of FA is effectively activated because of the active excitation effect of FGD and other added components, so the ettringite in harden cement paste is significantly found. Therefore, the application of FGD-FA composite mineral admixture can consume a lot of industrial wastes discharged from the power plant, and it has excellent effect of hydration and low-cost.
