P ] 1 1 O ct 2 00 5 Energy concentration and brittle crack propagation
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چکیده
The purpose of this paper is to fill the gap between the classical treatment of brittle fracture mechanics and the new idea of considering the crack evolution as a free discontinuity problem. Griffith and Irwin crite-rions of crack propagation are studied and transformed in order to be no longer dependent on any prescription of the geometry of the crack during its evolution. The inequality contained in theorem 6.1. represents the link between generalized Irwin and Griffith criterions of brittle crack propagation. The physical meaning of this inequality is explained in the last section.
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