Splitting Tensile Strength of Fly Ash Activated by Hydrothermal Hot-Pressing Process
Publication: Journal of Materials in Civil Engineering
Volume 21, Issue 8
Abstract
Fly ash is normally solidified by strong alkaline solutions at room or moderate temperatures. In this study, an innovative process of recycling fly ash (both Class F and Class C) into potential construction materials with superior mechanical properties is investigated. This innovative process involves chemical activation, hydrothermal reaction (hence, heat and moisture), and hot pressing. The emphasis is on the synergistic effects. Several key parameters—such as treatment temperature, duration of process, and amount of chemical activator—are evaluated critically. The results confirm that fly ash can be solidified and specimens show splitting tensile strengths of about by hydrothermal hot pressing alone. With a small amount of chemical activator (NaOH), the tensile strength can reach as high as .
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Acknowledgments
The writers are grateful to the Department of Energy (DOE)DOE for funding this project (Project No. CBRCM14, Program Manager Dr. P. Chugh) and to Mr. Gregory H. Keenan of the American Electric Power Energy Services, for providing the Class C and Class F fly ash used in this study.
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Information & Authors
Information
Published In
Journal of Materials in Civil Engineering
Volume 21 • Issue 8 • August 2009
Pages: 356 - 361
Copyright
© 2009 ASCE.
History
Received: Jun 28, 2006
Accepted: Jan 22, 2009
Published online: Jul 15, 2009
Published in print: Aug 2009
Notes
Note. Associate Editor: Kolluru V. Subramanian
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