Effect of Mechanically and Chemically Activated Iron Tailings on Strength and Pore Structure of Foamed Concrete

Objective To enhance the utilization rate of iron tailings and produce new green building materials, iron tailings powder was obtained through mechanical and chemical activation. This powder was used as an active admixture and mixed with cement through chemical foaming to prepare foamed concrete. Method Through orthogonal experiment, the 28 d compressive strength was used as the experimental index, and the optimal ratio was determined as follows: iron tailing powder 10%, cement 90%, hydrogen peroxide 2.5%, cetyltrimethyl ammonium bromide 0.375%, water-cement ratio 0.55. On the basis of determining the ratio of raw materials, the effects of iron tailing powder content on the strength, thermal conductivity, hydration products and pore structure of foamed concrete were studied. Result Addition of 10% iron tailings can promote the hydration reaction of cement, produce more hydration products, improve the pore structure of foamed concrete, and then increase the strength of foamed concrete. Conclusion With the further increase of iron tailings, the strength of foamed concrete gradually decreases. Moreover, the addition of iron tailings will reduce its thermal insulation performance.