矿渣基胶凝材料开发和充填体强度与流变特性研究

Development of Slag-based Cementitious Materials and Study on Strength and Rheological Properties of Backfill

针对中关铁矿高泥尾砂充填骨料,开展了矿渣基胶凝材料试验研究。通过矿渣基胶凝材料胶结体强度试验,获得复合激发剂配比为熟料10%、脱硫石膏15%,矿渣基胶凝材料激发剂与矿渣微粉之比为1∶3。利用该新型胶凝材料,分别采用1∶4和1∶8两种胶砂比,进行尾砂胶结体强度验证试验。结果表明,胶砂比为1∶4的全尾砂胶结体28 d强度大于2.5 MPa,可满足中关铁矿一步骤采场的充填体强度的要求;胶砂比为1∶8的全尾砂胶结体强度大于1.5 MPa,可以满足二步骤矿柱采场的充填体强度要求。最后针对中关铁矿高泥尾砂,开展了不同胶砂比和料浆浓度的胶结充填体强度和充填料浆的流变特性试验,满足揭示了矿渣基胶凝材料胶结体强度和料浆流变特性的变化规律,为新型胶凝材料在中关铁矿应用奠定了基础。

In view of the high-mud tailings filling aggregate in Zhongguan Iron Mine, the experimental study of slag-based cementitious material was carried out. Through the strength test of the backfill with slag-based cementitious material, the ratio of composite activator was 10% of clinker and 15% of desulfurization gypsum, and the ratio of the activator to slag powder was 1∶3.Through using the new cementitious material, the strength verification test of backfill was carried out with two cementitious ratios of 1∶4 and 1∶8.The results show that the strength of the whole tailings cemented body with cementing ratio of 1∶4 is greater than 2.5 MPa in 28 d, which meets the strength requirements of the backfill in one-step stope of Zhongguan Iron Mine. The strength of the whole tailings cemented body with cementing ratio of 1∶8 is greater than 1.5 MPa, which meets the strength requirements of the backfill in two-step pillar mining. Finally, according to the high-mud tailings, the tests on the strength of cemented backfill and the rheological properties of filling slurry with different cemented-sand ratios and slurry concentrations were carried out, thus revealing the change rule of the strength and the rheological properties, which laid a foundation for the application of this new cemented material in Zhongguan Iron Mine.