Effect of ambient curing on the mechanical properties of fly ash-silica fume geopolymer concrete
Golan ALRICH, Manjusha MURALEEDHARAN, Deepak Satyanarayan IRUKULLAWAR
Abstract. This research explores how curing at normal room temperature affects the performance of fly ash-silica fume geopolymer concrete, developed as a greener alternative to traditional Portland cement. While most studies on geopolymers rely on heat curing to achieve strength, this work shifts the focus to ambient curing (30 ± 2°C), reflecting real on-site conditions where applying heat is not always feasible. The binder system combined Class F fly ash with silica fume, activated by a mixture of sodium hydroxide and sodium silicate, with three proportions tested: 50:50, 60:40, and 80:20. After 28 days of curing at room temperature, results showed that the mixes developed significant strength, proving that heat is not essential for high-quality geopolymer concrete. Among the three, the 60:40 blend offered the best overall performance, reaching 40 MPa in compressive strength and 3.9 MPa in split tensile strength, well above conventional M30 concrete. Workability also varied with mix design; higher fly ash content improved flow, while higher silica fume content reduced slump but contributed to denser microstructure and better strength. These findings underline the practical potential of ambient curing in making geopolymer concrete both strong and sustainable. By eliminating the need for heat curing, this approach reduces energy use, carbon emissions, and cost, while offering construction-ready solutions for real-world projects. Overall, the study shows that fly ash-silica fume geopolymer concrete with 60:40 blend can deliver excellent mechanical properties under ambient conditions, making it a promising path toward low-carbon construction.
Keywords
Geopolymer, Fly Ash, Silica Fume, Ambient Curing, Compressive Strength, Split Tensile Strength
Published online 6/20/2026, 8 pages
Copyright © 2026 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Golan ALRICH, Manjusha MURALEEDHARAN, Deepak Satyanarayan IRUKULLAWAR, Effect of ambient curing on the mechanical properties of fly ash-silica fume geopolymer concrete, Materials Research Proceedings, Vol. 67, pp 824-831, 2026
DOI: https://doi.org/10.21741/9781644904176-114
The article was published as article 114 of the book Climate Action and Sustainability
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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