The Use of Slag and Red Mud for the Synthesis of a Slag-Based Cementitious Material

A large amount of metallurgical slag storage occupies land and wastes a lot of resources. Therefore, this study uses slag and red mud (RM) as the main raw materials, sodium silicate, and sodium hydroxide (NaOH) as the composite alkaline activators, the slag-based cementitious materials were prepared by the secondary mixed grinding method. The mechanical properties of the cementitious materials were characterized and analyzed. The results show that when the ratio of slag to RM in the cementing material is 8:2, the strength increases initially and then decreases with the increase of the content of the alkaline activator. Meanwhile, the content of the alkaline activator is 10% (mass fraction), and the 28-day compressive strength of the sample is up to 67.8MPa, which meets the requirements of slag cement with a 42.5 strength grade.