In Situ Elevated Temperature Testing of Fly Ash Based Geopolymer Composites
Les Vickers1, Zhu Pan2, Zhong Tao3
1Geopolymer Research Group, John de Laeter Centre, Curtin University, GPO Box U1987, Perth WA 6845, Australia. vickers4@bigpond.net.au.
Materials (Basel, Switzerland)
|August 5, 2017
Summary
Fly ash geopolymers with alumina aggregate show improved high-temperature performance. Applied stress lowers viscous flow temperature, while alumina reduces thermal conductivity, enhancing fire resistance and reducing cracks.
Area of Science:
- Materials Science
- Geopolymer Chemistry
- Civil Engineering
Background:
- Geopolymers are advanced inorganic polymers with potential for high-temperature applications.
- Understanding geopolymer behavior under elevated temperatures is crucial for structural integrity.
- Fly ash-based geopolymers offer a sustainable alternative to traditional binders.
Purpose of the Study:
- To investigate the high-temperature performance of fly ash-based geopolymers filled with alumina aggregate.
- To determine the onset temperature of viscous flow under load and no-load conditions.
- To evaluate the impact of alumina aggregate and reduced water content on thermal properties and fire resistance.
Main Methods:
- In situ elevated temperature investigations.
- Compressive strength and short-term creep tests.
- Fire testing using the standard cellulose curve.
Main Results:
- Applied stress reduced the onset temperature of viscous flow compared to no-load conditions.
- Compressive strength increased at elevated temperatures due to viscous flow and sintering.
- Alumina aggregate and reduced water content decreased thermal conductivity, leading to earlier dehydration and reduced cracking.
Conclusions:
- Fly ash geopolymers with alumina exhibit enhanced high-temperature stability and fire resistance.
- The addition of alumina aggregate and optimized water content are key to improving thermal performance.
- Reduced thermal gradients contribute to improved crack resistance during fire exposure.
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