Abstract:In order to explore recovery and utilization of red mud, red mud based alkali-activated cementitious materials were prepared with sintered red mud as active materials and different modulus of water glass solution as activator. Mechanical properties and pore structure characteristics of cementitious materials were tested. Micro mechanism was explored by XRD, SEM and DTA. The results show that modulus of water glass has a big influence on properties of cementitious materials. Water glass with modulus of 0.96 has the best excitation effect, and compressive strength reaches 10.21 MPa in 28 d. Main source of strength of hardened specimen is calcium silicate hydrate. Higher strength materials have more fine microstructures and much more alkali-activated products.