[article] 
inJournal of engineering mechanics > Vol. 135 N°2 (Février 2009) . - pp. 78-84

Titre :	Universal size effect law and effect of crack depth on quasi-brittle structure strength
Type de document :	texte imprimé
Auteurs :	Zdenek P. Bazant, Auteur
Article en page(s) :	pp. 78-84
Note générale :	Mécanique appliquée
Langues :	Anglais (eng)
Mots-clés :	Size effect Fracture Cracking Notches Structural reliability Concrete.
Résumé :	In cohesive fracture of quasi-brittle materials such as concrete, rock, fiber composites, tough ceramics, rigid foams, sea ice, and wood, one can distinguish six simple and easily modeled asymptotic cases: the asymptotic behaviors of very small and very large structures, structures failing at crack initiation from a smooth surface and those with a deep notch or preexisting deep crack, the purely statistical Weibull-type size effect, and the purely energetic (deterministic) size effect. Size effect laws governing the transition between some of these asymptotic cases have already been formulated. However, a general and smooth description of the complex transition between all of them has been lacking. Here, a smooth universal law bridging all of these asymptotic cases is derived and discussed. A special case of this law is a formula for the effect of notch or crack depth at fixed specimen size, which overcomes the limitations of a recently proposed empirical formula by Duan et al., 2003, 2004, 2006.
DEWEY :	620.1
ISSN :	0733-9399
En ligne :	http://ascelibrary.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JENMDT000 [...]

[article] Universal size effect law and effect of crack depth on quasi-brittle structure strength [texte imprimé] / Zdenek P. Bazant, Auteur . - pp. 78-84.
Mécanique appliquée
Langues : Anglais (eng)
in Journal of engineering mechanics > Vol. 135 N°2 (Février 2009) . - pp. 78-84

Mots-clés :	Size effect Fracture Cracking Notches Structural reliability Concrete.
Résumé :	In cohesive fracture of quasi-brittle materials such as concrete, rock, fiber composites, tough ceramics, rigid foams, sea ice, and wood, one can distinguish six simple and easily modeled asymptotic cases: the asymptotic behaviors of very small and very large structures, structures failing at crack initiation from a smooth surface and those with a deep notch or preexisting deep crack, the purely statistical Weibull-type size effect, and the purely energetic (deterministic) size effect. Size effect laws governing the transition between some of these asymptotic cases have already been formulated. However, a general and smooth description of the complex transition between all of them has been lacking. Here, a smooth universal law bridging all of these asymptotic cases is derived and discussed. A special case of this law is a formula for the effect of notch or crack depth at fixed specimen size, which overcomes the limitations of a recently proposed empirical formula by Duan et al., 2003, 2004, 2006.
DEWEY :	620.1
ISSN :	0733-9399
En ligne :	http://ascelibrary.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JENMDT000 [...]