Materials and Structures

, Volume 34, Issue 5, pp 260–265 | Cite as

Influence of size on fracture energy of concrete

  • B. Trunk
  • F. H. Wittmann
Scientific Reports

Abstract

Concrete structures frequently exhibit cracks. In order to investigate the influence of cracks on durability and the remaining load bearing capacity of buildings, fracture mechanics models can be used. For materials like concrete non-linear models for example the fictitious crack model introduced by Hillerborg, Modéer and Petersson [1] or the crack band model proposed by Bažant and Oh [2] are able to describe crack formation and propagation in a realistic way. But it has been observed, that the parameters of these models depend both, on structural size and geometry. In this paper a simple model to explain the nature of size and geometry dependence of the specific fracture energy is presented. The model is evaluated with experimental data from Trunk and Wittmann [2,4,5].

Keywords

Fracture Energy Concrete Structure Size Dependence Fracture Process Zone Ligament Length 

Résumé

Les constructions en béton présentent souvent des fissures. Pour montrer l'influence de ces fissures sur la durabilité et la capacité portante restante de la construction, on peut appliquer des modèles de la mécanique de la rupture. Dans le cas de matériaux de construction comme le béton, des modèles non linéaires, tels que le modèle de la fissure fictive de Hillerborg, Modéer et Petersson [1] ou le modèle de la bande microfissurée de Bažant et Oh [2], sont capables de décrire la formation et la propagation de fissures d'une façon réaliste. Mais on a constaté que les paramètres de l'élément de construction. Dans cette contribution, on présente un modèle simple permettant d'expliquer la nature de ces dépendances sur l'énergie spécifique, de la rupture. Le modèle a été validé par des résultats expérimentaux obtenus par Trunk et Wittmann [2, 4, 5].

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Copyright information

© RILEM 2001

Authors and Affiliations

  • B. Trunk
    • 1
  • F. H. Wittmann
    • 1
  1. 1.Institute for Building MaterialsSwiss Federal Institute of TechnologyZürichSwitzerland

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