Effects of restraint on expansion due to delayed ettringite formation
- Universite de Toulouse, UPS, INSA, LMDC (Laboratoire Materiaux et Durabilite des Constructions), 135, avenue de Rangueil, F-31 077 Toulouse Cedex 04 (France)
- Laboratoire Materiaux et Durabilite des Constructions, Department of Civil Engineering, University of Constantine (Algeria)
Delayed ettringite formation (DEF) is a chemical reaction that causes expansion in civil engineering structures. The safety level of such damaged structures has to be reassessed. To do this, the mechanical conditions acting on DEF expansions have to be analysed and, in particular, the variation of strength with expansion and the effect of restraint on the DEF expansion. This paper highlights several points: DEF expansion is isotropic in stress-free conditions, compressive stresses decrease DEF expansion in the direction subjected to restraint and lead to cracks parallel to the restraint, and expansion measured in the stress-free direction of restrained specimens is not modified. Thus restraint causes a decrease of the volumetric expansion and DEF expansion under restraint is anisotropic. Moreover, the paper examines the correlation between DEF expansion and concrete damage, providing data that can be used for the quantification of the effect of stresses on DEF induced expansion.
- OSTI ID:
- 21596973
- Journal Information:
- Cement and Concrete Research, Vol. 42, Issue 7; Other Information: DOI: 10.1016/j.cemconres.2012.04.001; PII: S0008-8846(12)00074-9; Copyright (c) 2012 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0008-8846
- Country of Publication:
- United States
- Language:
- English
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