Mathematical and numerical aspects of an elasticity-based local approach to fracture
Keywords:
:jracture, damage, fatigue, localisation, fini te element method, mesh sensitivityAbstract
In local approaches ta fracture, crack initiation and growth are regarded as the ultimate consequences of a graduai, localloss of mate rial integrity. Standard degradation models, however, are unable to deal with localisation instabilities and the singular strains at the crack tip. As a consequence, finite element analyses become highly sensitive to the spatial discretisation. Adding nonlocal tenns ta the models enhances the ir ability ta de scribe fracture processes. An essential raie is played by the treatment of the boundary of the equilibrium problem, particularly the internai boundary which re presents the crack contour. If the appropriate boundary conditions are applied and the crack region is removed from the discrete equilibrium problem, fini te element analyses become mesh-objective.
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