关键词: 流态胶凝材料, 充填开采, 流动度, 抗压强度

Abstract: In order to simplify the process of cementitious material production and reduce the cost of filling,the fluid cementitious materials (FCM) were used to replace powder cementitious materials (PCM) for the solidification of iron tailings. The properties were investigated using fluidity tests,strength tests and water absorption tests for the specimens of solidified iron tailing (SIT) with two kinds of cementitious materials of PCM and FCM. The binding mechanism of SIT was analyzed using XRD and SEM techniques. For the specimen of SIT with the solid tailing content being 70% and the cement-to-tail ratio being 1 ∶10,the 3-day compressive strength (0. 87 MPa) of the specimens using PCM as tailing binder was about 0. 3 MPa higher than that using FMC. The difference of 7 d compressive strength was decreasing between two SIT specimens with PCM and FCM,and there was no significant difference for their 28 d compressive strengths. The flowability of the filling tailing with the addition of FCM was increased by 7. 4% compared to that with the addition of PCM. It indicated that the using of FCM could facilitate pumping and filling of iron tailing slurry without affecting the 28 d mechanical properties of SIT′s. XRD and SEM analysis showed that the hydration reaction of FCM was more benefit to the growth of ettringite.

Key words: fluid cementitious material,filling mining,fluidity,compressive strength