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arXiv · 1505.01018

Perfect plasticity with damage and healing at small strains, its modelling, analysis, and computer implementation

Tomáš Roubíček·Jan Valdman
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Abstract

The quasistatic, Prandtl-Reuss perfect plasticity at small strains is combined with a gradient, reversible (i.e. admitting healing) damage which influences both the elastic moduli and the yield stress. Existence of weak solutions of the resulted system of variational inequalities is proved by a suitable fractional-step discretisation in time with guaranteed numericalstability and convergence. After finite-element approximation, this scheme is computationally implemented and illustrative 2-dimensional simulations are performed. The model allows e.g. for application in geophysical modelling of re-occurring rupture of lithospheric faults. Resulted incremental problems are solved in MATLAB by quasi-Newton method to resolve elastoplasticity component of the solution while damage component is obtained by solution of a quadratic programming problem.

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Tomáš Roubíček, Jan Valdman. 2015-05-05. Perfect plasticity with damage and healing at small strains, its modelling, analysis, and computer implementation. https://arxiv.org/abs/1505.01018

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