Abstract: The reasonable ratio of T.C， a new type cementitious material， incorporated into the unclassified tailings-cemented process， and its effect on the stability of the heap are investigated by laboratory orthogonal test， numerical simulations and other methods. The slag， lime， gypsum， sulfoaluminate cements and clinker are used as raw materials for cementitious materials. The influencing level of various factors on the strength of the cemented body are listed as slag， lime， sulphur-aluminum cement， gypsum by the orthogonal test， and the best ratio of the new type cementitious material T.C shows like slag: lime: gypsum: sulfoaluminate cement: clinker of 70∶6∶10∶4∶10. A comprehensive comparison on the strength of consolidated cement bodies is carried out under the action of ordinary portland cement（P.O.42.5）， slag cement（P.S.32.5）， and new type cementitious material T.C. It was found that the effect of the new type cementitious material T.C is obviously better than that of ordinary portland cement and slag cement in early strength and late strength. Based on the strength reduction method and FLAC3D， the stability of the heap is analyzed. And it is suggested that the height of the heap should be less than 50 m， the stacking angle be less than 60°， the slurry concentration be between 76% and 78%， and the ratio of cement to sand be between 1∶12 and 1∶9.

Key words: Tailings&rsquo, cementation, New type cementitious materials T.C, Stability of the heap, Numerical simulation