Properties of Blended Cement Containing Iron Tailing Powder at Different Curing Temperatures

• Published in: Materials Vol. 15; no. 2; p. 693
• Main Authors: Wang, Heng, Han, Fanghui, Pu, Shaochang, Zhang, Hongbo
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 17-01-2022; MDPI
• Subjects: Age; blended cement; Cement; Compressive strength; Concrete; Curing; Exothermic reactions; Heat; High temperature; Hydration; hydration heat; Investigations; Iron; Iron compounds; iron tailing powder; Mechanical properties; microstructure; Moisture content; Particle size; Portland cements; Raw materials; Sand & gravel; Slaked lime; Tailings; China; compressive strength; blended cement; hydration heat; microstructure; iron tailing powder
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma15020693

The properties of blended cement containing 0%, 20%, and 50% iron tailing powder (ITP) at 20 °C and 60 °C were investigated by determining the hydration heat, microstructure, and compressive strength. The addition of ITP decreases the exothermic rate and cumulative hydration heat of blended cement at 20 °C. The high temperature increases the hydration rate and leads to the hydration heat of blended cement containing 20% ITP higher than that of Portland cement. Increasing the amount of ITP decreases the non-evaporable water content and Ca(OH)
content as well as compressive strength at both of the two studied temperatures. The addition of ITP coarsens the early-age pore structure but improves the later-age pore structure at 20 °C. The high temperature significantly improves the early-age properties of blended cement containing ITP, but it is detrimental to the later-age properties development. The reaction of ITP is limited even at high temperature. The large ITP particles bond poorly with surrounding hydration products under early high-temperature curing condition. The properties of blended cement containing a large amount of ITP are much poorer at high temperature.