铁尾矿粉作为掺合料制备高强混凝土的研究

摘要

研究了不同掺量铁尾矿粉对高强混凝土强度的影响，并通过扫描电镜和压汞仪对混凝土的水化产物和孔结构分布特性进行了分析。结果表明，铁尾矿替代胶凝材料20％和30％时，其混凝土达到C60混凝土的强度等级。当铁尾矿为40％时，其混凝土试样达到C50混凝土的强度等级。不同铁尾矿掺量混凝土试样中的孔主要以20~50 nm的少害孔为主。不同掺量铁尾矿粉的孔隙率、平均孔径等有所不同。铁尾矿掺量20％和30％试样的水化产物较为密实，而铁尾矿掺量40％的试样水化产物较为疏松。%The effect of iron tailing powder on the strength of high strength concrete was studied. The hydration products and pore struc-ture distribution of concrete was analyzed by SEM and MIP. The results show that the concrete strength grade reaches C60 when the re-placement of iron tailings for 20% and 30% of cementitious material,and the concrete strength grade reaches C50 when the replacement of iron tailings for 40% of cementitious material. The pore in concrete is mainly the 20~50 nm. When the content of iron tailings in con-crete changes,the power porosity and average pore size in concrete are different. The hydration products is dense when the replacement of iron tailings for 20% and 30% of cementitious material,and the hydration products is loose when the replacement of iron tailings for 40%of cementitious material.