Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.3/95611

Title

Damage behavior of geopolymer composites exposed to elevated temperatures

Author(s)

Kong, Daniel L. Y.;  Sanjayan, Jay G.

Abstract

This paper presents a study on geopolymers and geopolymer/aggregate composites made with class F fly ash. Samples were heated up to 800 °C to evaluate strength loss due to thermal damage. The geopolymers exhibited strength increases of about 53% after temperature exposure. However, geopolymer/aggregate composites with identical geopolymer binder formulations decreased in strength by up to 65% after the same exposure. Test data from dilatometry measurements of geopolymers and aggregates provides an explanation for this behavior. The tests show that the aggregates steadily expanded with temperature, reaching about 1.5-2.5% expansion at 800 °C. Correspondingly, the geopolymer matrix undergoes contraction of about 1% between 200 °C and 300 °C and a further 0.6% between 700 °C and 800 °C. This apparent incompatibility is concluded to be the cause of the observed strength loss. This study presents the results of 15 different geopolymer combinations (i.e. mixture proportions, curing and age) and four different aggregates.

Publication type

Journal article

Source

Cement and Concrete Composites, Vol. 30, no. 10 (Nov 2008), pp. 986-991

Publication year

2008

FOR Code(s)

0905 Civil Engineering;  1202 Building

Keyword(s)

Agglomeration;  Aggregates;  Class-F fly ash;  Concrete aggregates;  Damage behaviors;  Dilatometry;  Elevated temperatures;  Fly ash;  Geopolymer binders;  Geopolymer composites;  Geopolymer matrixes;  Geopolymers;  Inorganic polymers;  Mixture proportions;  Strength losses;  Temperature exposures;  Test datums;  Thermal damages

Publisher

Pergamon

ISSN

0958-9465

Publisher URL

http://dx.doi.org/10.1016/j.cemconcomp.2008.08.001

Copyright

Copyright © 2008 Elsevier Ltd. All rights reserved.

Peer reviewed