Publication detail

EFFECT OF THE AGGREGATE TYPE ON THE PROPERTIES OF ALKALI-ACTIVATED SLAG SUBJECTED TO HIGH TEMPERATURES

ROVNANÍK, P. DUFKA, A.

Original Title

EFFECT OF THE AGGREGATE TYPE ON THE PROPERTIES OF ALKALI-ACTIVATED SLAG SUBJECTED TO HIGH TEMPERATURES

Type

journal article in Web of Science

Language

English

Original Abstract

High temperatures present a risk of destruction for most silicate based construction materials. Although these materials are not flammable, they lose their properties due to a thermal decomposition. In contrast to ordinary Portland cement based materials, alkali-activated slag exhibits better thermal stability when exposed to temperatures up to 1200 °C. Due to its different porosity it is less susceptible to spalling. However, the properties of composites after high temperature treatment depend also on the stability of aggregates. The effect of two different types of aggregate (quartz and chamotte) on the residual mechanical properties and microstructure of alkali-activated slag mortars exposed to 200–1200 °C is presented in this study. The results showed an improved mechanical performance of thermally stable chamotte aggregate at temperatures above 600 °C. Quartz is transformed at 573 °C to high quartz causing volume instability and consequently a strength deterioration. Although chamotte also contains some quartz phase, the reaction of mullite with alkalis from the matrix leads to the formation of albite and anorthite which makes the material tougher, and thus, compensating the negative effect of quartz.

Keywords

alkali-activated slag, high temperatures, chamotte, quartz, strength, microstructure

Authors

ROVNANÍK, P.; DUFKA, A.

RIV year

2015

Released

1. 10. 2015

ISBN

1580-2949

Periodical

Materiali in tehnologije

Year of study

49

Number

5

State

Republic of Slovenia

Pages from

709

Pages to

713

Pages count

5

BibTex

@article{BUT117313,
  author="Pavel {Rovnaník} and Amos {Dufka}",
  title="EFFECT OF THE AGGREGATE TYPE ON THE PROPERTIES OF ALKALI-ACTIVATED SLAG SUBJECTED TO HIGH
TEMPERATURES",
  journal="Materiali in tehnologije",
  year="2015",
  volume="49",
  number="5",
  pages="709--713",
  doi="10.17222/mit.2014.116",
  issn="1580-2949"
}