Size-effect prediction from effective crack model for plain concrete

  • B. L. Karihaloo
  • P. Nallathambi
Article

Abstract

The size effect predicted by the authors' effective crack model is compared with that of the fictitious crack model (cohesive crack model) using the methodology proposed by Planas and Elices. It is shown that for notched three-point bend laboratory-size speciments., the predictions of the two models are totally indistinguishable from one another. However, the fracture loads predicted by the two models for increasing sizes are still very close so that in the asymptotic limit (of infinite size) the prediction differ by no more than about 17%.

Keywords

Linear Elastic Fracture Mechanic Fracture Load Critical Stress Intensity Factor Cohesive Crack Model Fictitious Crack Model 

Résumé

On compare l'effet d'échelle prévu par le modèle de fissuration établi par les auteurs avec le modèle de fissuration fictive (modèle de fissuration cohérente) en utilisant la méthodologie proposée par Planas et Elices. On montre que pour les corps d'épreuve entaillés pour l'essai de flexion ‘3 points’, les prévisions de deux modèles ne se démarquent absolument pas l'une de l'autre. Cependant, les charges de rupture prévues par les modèles pour des dimensions croissantes sont encore très proches, de sorte qu'à la limite asymptotique (à l'infini), l'écart entre les prévisions ne dépasse pas 17% environ.

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Copyright information

© RILEM 1990

Authors and Affiliations

  • B. L. Karihaloo
    • 1
  • P. Nallathambi
    • 1
  1. 1.School of Civil and Mining EngineeringUniversity of SydneyAustralia

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