Publication detail

Use of X-ray CT for analysis of concretes exposed to high temperatures

BODNÁROVÁ, L. SITEK, L. SOUČEK, K. STAŠ, L.

Original Title

Use of X-ray CT for analysis of concretes exposed to high temperatures

English Title

Use of X-ray CT for analysis of concretes exposed to high temperatures

Type

conference paper

Language

en

Original Abstract

Concrete has many advantageous properties, e.g. inflammability or low temperature conductivity. However, when a concrete construction is exposed to high temperatures, it loses its load-bearing capacity, especially in surface layers which are loaded at most. A serious problem represents the so-called explosive spalling which is caused by the combination of increasing pressure in inner pores and inner compressive stresses originating from material expansion at higher temperatures. Spalling of a concrete layer leads to weakening of the concrete cross section of a reinforced construction and, in some cases, to exposure of steel reinforcement to temperatures above the critical level. Defects can be so serious that the complete construction gets destroyed. Design of a concrete mixture with resistance to thermal exposure for a certain period of time has been classified among the passive fire protection methods. Basic composition of the cement concrete can be problematic, as it is the composite material consisting of two markedly different components, i.e. the cement paste and aggregate. When exposed to high temperatures, both components behave differently and their physical, chemical and mechanical properties change (for example Mindeguia, J.C., 2013)

English abstract

Concrete has many advantageous properties, e.g. inflammability or low temperature conductivity. However, when a concrete construction is exposed to high temperatures, it loses its load-bearing capacity, especially in surface layers which are loaded at most. A serious problem represents the so-called explosive spalling which is caused by the combination of increasing pressure in inner pores and inner compressive stresses originating from material expansion at higher temperatures. Spalling of a concrete layer leads to weakening of the concrete cross section of a reinforced construction and, in some cases, to exposure of steel reinforcement to temperatures above the critical level. Defects can be so serious that the complete construction gets destroyed. Design of a concrete mixture with resistance to thermal exposure for a certain period of time has been classified among the passive fire protection methods. Basic composition of the cement concrete can be problematic, as it is the composite material consisting of two markedly different components, i.e. the cement paste and aggregate. When exposed to high temperatures, both components behave differently and their physical, chemical and mechanical properties change (for example Mindeguia, J.C., 2013)

Keywords

X-ray tomography, concrete, cement paste, aggregate, high temperature

RIV year

2014

Released

25.06.2014

Location

Ostrava

ISBN

978-80-86407-49-4

Book

GECO 2014

Edition number

5

Pages from

87

Pages to

88

Pages count

2

Documents

BibTex


@inproceedings{BUT114051,
  author="Lenka {Bodnárová} and Libor {Sitek} and Kamil {Souček} and Lubomír {Staš}",
  title="Use of X-ray CT for analysis of concretes exposed to high temperatures",
  annote="Concrete has many advantageous properties, e.g. inflammability or low temperature conductivity. However, when a concrete construction is exposed to high temperatures, it loses its load-bearing capacity, especially in surface layers which are loaded at most. A serious problem represents the so-called explosive spalling which is caused by the combination of increasing pressure in inner pores and inner compressive stresses originating from material expansion at higher temperatures. Spalling of a concrete layer leads to weakening of the concrete cross section of a reinforced construction and, in some cases, to exposure of steel reinforcement to temperatures above the critical level. Defects can be so serious that the complete construction gets destroyed. Design of a concrete mixture with resistance to thermal exposure for a certain period of time has been classified among the passive fire protection methods. Basic composition of the cement concrete can be problematic, as it is the composite material consisting of two markedly different components, i.e. the cement paste and aggregate. When exposed to high temperatures, both components behave differently and their physical, chemical and mechanical properties change (for example Mindeguia, J.C., 2013)",
  booktitle="GECO 2014",
  chapter="114051",
  howpublished="electronic, physical medium",
  year="2014",
  month="june",
  pages="87--88",
  type="conference paper"
}