Composite admixtures were prepared using iron tailings,fly ash,and lithium slag as raw materials,replacing cement with their equal mass.Multi element solid waste concrete was prepared using iron tailings waste as coarse aggregate and iron tail-ings sand as fine aggregate.The effects of water cement ratio,composite admixture dosage,and preparation ratio on concrete strength and pore structure were studied.The results show that the 28 d strength of concrete prepared with 30%composite admixture and 1:2∶2 ratio of iron tailing power,fly ash and lithium slag power is 50.2 MPa,which is the highest.The higher pozzolanic activity of lithium slag power and fly ash promotes the hydration of cement near the interfacial transition zone,which is combined with the filling effect of iron tailing power.The micro-aggregate effect of fly ash and the micro-expansion of lithium slag power,and im-proves the density of concrete.In general,the coupling between the composite admixture and the synergistic hydration of the admix-ture and cement optimize the pore structure of the concrete and thus improve the macro strength.
关键词
铁尾矿/混凝土/抗压强度/孔结构/界面过渡区
Key words
iron tailings/concrete/compressive strength/pore structure/interfacial transition region
维普
万方数据