提钛炉渣-铁基全尾砂-水泥胶结充填体配比实验研究

Experimental study on the ratio between ti-bearing blast furnace slag-iron-based full tailing sand and cement in cementitious filling

为研究提钛炉渣替换水泥全尾砂胶结充填体的最佳配比及力学性能,以提钛炉渣(TBS)、铁基全尾砂(IFT)和水泥(P.O 42.5R)为实验材料,在分析该提钛炉渣的粒径级配组成、成分等物理化学特性的基础上,制备灰砂比1∶4、1∶6、1∶8和提钛炉渣掺入替换比为40%、50%、60%、70%、80%的充填体试样,测定了养护龄期分别为7 d、14 d和28 d时的充填体单轴抗压强度。实验结果表明:充填体的抗压强度与养护期龄正相关;相同养护时间下,充填体的单轴抗压强度随着灰砂比的增大而增大;随提钛炉渣替换比增大,充填体28 d强度先增大后减小;当提钛炉渣替换比为50%时,灰砂比1∶8、1∶6、1∶4的充填体28 d抗压强度分别为1.8 MPa、2.5 MPa、4.0 MPa,均超过未添加提钛炉渣的试块强度,表明掺入提钛炉渣对充填体的28 d强度具有明显的提升作用。研究结果表明,提钛炉渣可开发为矿山充填胶凝材料,从而降低矿山充填成本。

This study investigated the optimal ratio and mechanical properties of iron-based full tailing sand(IFT)and cement(P.O42.5R)as experimental materials,with the addition of the Ti-bearing Blast Furnace Slag(TBS),in full tailing sand cemented filling material.The physical and chemical properties of TBS,including particle size gradation composition and chemical composition,were analyzed.Filling specimens were prepared with sand-cement ratios of 1∶4,1∶6,and 1∶8,and TBS replacement ratios of 40%,50%,60%,70%,and 80%.The uniaxial compressive strength of the filling specimens was measured after curing for 7,14,and 28 days.The experimental results demonstrated a positive correlation between the compressive strength of the filling and the curing time.Additionally,under the same curing time,the uniaxial compressive strength of the filling increased with the increase of the sand-cement ratio.With an increase in the replacement percentage of TBS,the strength of the filling initially increased and then decreased at 28 days.Notably,when the TBS replacement ratio was 50%,the com-pressive strength of the filling with ratios of 1∶8,1∶6,and 1∶4 after 28 days of curing was 1.8 MPa,2.5 MPa,and 4.0 MPa,respectively.All of these values exceeded the strength of the specimens without TBS,indicating that the addition of TBS significantly improved the compressive strength of the filling at 28 days.The research results demonstrate that TBS can be developed as a cementitious material for mine backfill,thereby reducing the cost of mine filling.