Necessary and sufficient fracture criteria for a composite with a brittle matrix. Part 1. Weak reinforcement
V. M. Kornev
Lavrent'ev Institute of Hydrodynamics, Siberian Division, Russian Academy of Sciences, Novosibirsk 630090
Pages: 467-474
Abstract
Fracture of a composite medium with a
brittle matrix is studied. The brittle
or plastic material of the reinforcing
elements is highly deformable. For
normal-rupture macrocracks, necessary
criteria of brittle strength and
sufficient criteria of quasibrittle
strength are proposed. Simple analytical
dependences of the macrocrack length on
the loading parameter, structural,
rigidity, and strength parameters of the
medium, and damage parameters of the
material of the components are obtained.
The critical loads for these criteria
may differ substantially even if the
reinforcement coefficient is small and
the material of reinforcing elements is
highly deformable. If the necessary
criterion is satisfied, crack extension
occurs and microcracks are formed in the
bonds of the structure located ahead of
the macrocrack tip. The number of
damaged bonds depends on the macrocrack
opening and characteristics of
postcritical deformation of the damaged
bonds.
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