High-temperature performance of slag-based Fe-rich alkali-activated materials
Ponomar, Vitalii; Adesanya, Elijah; Ohenoja, Katja; Illikainen, Mirja (2022-09-07)
Ponomar, V., Adesanya, E., Ohenoja, K., & Illikainen, M. (2022). High-temperature performance of slag-based Fe-rich alkali-activated materials. Cement and Concrete Research, 161, 106960. https://doi.org/10.1016/j.cemconres.2022.106960
© 2022 The Authors. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
https://creativecommons.org/licenses/by/4.0/
https://urn.fi/URN:NBN:fi-fe2022120870130
Tiivistelmä
Abstract
Fe-rich alkali-activated materials have been studied for their suitability for high-temperature application up to 1000 °C. The evolution of compressive strength, mineral composition and microstructure was monitored using FT-IR, XRD, TGA and SEM-WDS for the pastes and mortars obtained by alkali activation of fayalite and wüstite non-ferrous slags. For both binders, the changes in compressive strength revealed moderate fluctuations below 400 °C due to water evaporation, a sharp drop in strength to 25 MPa at 600 °C due to collapse of the original gel structure, and reinforcement of the strength above 600 °C due to sintering densification and formation of gehlenite-åkermanite or diopside-albite ceramic. An extensive reaction of the quartz aggregate with a sodium-rich binder resulted in the formation of an iron silicate phase that contributed to a further increase in the strength up to 70 MPa by increasing both temperature and time of heating.
Kokoelmat
- Avoin saatavuus [31941]