Sorne aspects of a gradient damage formulation
Keywords:
Continuum Damage Mechanics, Gradient Regularizarion, Finite Element MethodAbstract
The paper discusses some theoretical and mmzerical aspects of a gradient damage formulation. Thereby, the main motivation is provided by localization computations whereby classical local continuum fomzulations fait ta produce physically meaningful and numerically com·erging results. Therefore, we propose a fomzulation in tem1s of the Helmholtzfree energy incorporating the gradient of the damage field, a dissipation potential and the postulate of max· imum dissipation. As a result the driving force conjugated ta damage evolution incorporates besides the strictl_v local energy release rate essentially the divergence of a vectorial damage jlzLL At the numerical side, besides balance of linear momentum, the algorithmic consistency condition has ta be solved in weakfonn.
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References
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