Cementitious activity optimization studies of iron tailings powder as a concrete admixture

The cementitious activity of iron tailings powder (ITP) as a concrete admixture is investigated and optimized in this study. When the specific surface area (SSA) of ITP is in the range of 450 - 550 m(2)/kg, the activity is larger than that of fly ash, and when SSA is 469 m(2)/kg, the activity reaches its largest value of 76.82%. The content of ITP should not exceed 30%. Chemical-mechanical activation increases the activity by only 4.82% which is comparable to a single mechanical activation. ITP role in a concrete admixture is in the physical filling of microaggregates. (C) 2020 Elsevier Ltd. All rights reserved.