Mechanical activated waste magnetite tailing as pozzolanic material substitute for cement in the preparation of cement products

• Published in: Construction & building materials Vol. 252; p. 119129
• Main Authors: Wu, Chun-Ran, Hong, Zhi-Qiang, Yin, Yun-He, Kou, Shi-Cong
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 20.08.2020
• Subjects: Mechanical properties; Pozzolanic activity; Rheological behaviour; Waste magnetite tailing; TG-DTA; NSFC; LOI; Mechanical properties; XRD; XRF; Waste magnetite tailing; Rheological behaviour; MWMT; SAI; SEM; WMT; Pozzolanic activity
• ISSN: 0950-0618; 1879-0526
• DOI: 10.1016/j.conbuildmat.2020.119129

[Display omitted] •Mechanical activated waste magnetite tailing (MWMT) was studied as cement additive.•Pozzolanic effect of MWMT in cementitious system was determined.•MWMT improves the rheological behaviour of fresh mortar.•MWMT adversely affects the mechanical properties of cement. This study investigated the effect of mechanical activated waste magnetite tailing (MWMT) as a pozzolanic material substitute for cement on the properties of cement-based products. The rheological behaviour (yield stress and plastic viscosity) of fresh mortar containing MWMT was investigated and approximated using the Bingham plastic model, and the mechanical properties (flexural and compressive strength) of mortar containing MWMT were studied. Results of the Frattini and strength activity index tests showed that MWMT was a low-activity pozzolanic material, consistent with the Ca(OH)2 content and mineral composition analysis. MWMT has a beneficial effect on the rheological behaviour of fresh mortar because the low specific surface area of MWMT overcomes the adverse effect of its rough and angular particles. The mechanical properties of mortar weaken as the MWMT content increases. However, the pozzolanic activity of MWMT enhances the rate at which the strength values increase as the MWMT content increases from 28 to 90 d.