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arXiv · 2202.10040

Phase-field fracture irreversibility using the slack variable approach

Ritukesh Bharali·Fredrik Larsson·Ralf Jänicke
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Abstract

In this manuscript, the phase-field fracture irreversibility constraint is transformed into an equality-based constraint using the slack variable approach. The equality-based fracture irreversibility constraint is then introduced in the phase-field fracture energy functional using the Lagrange Multiplier Method and the Penalty method. Both methods are variationally consistent with the conventional variational inequality phase-field fracture problem, unlike the history-variable approach. Thereafter, numerical experiments are carried out on benchmark problems in brittle and quasi-brittle fracture to demonstrate the efficacy of the proposed method.

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Ritukesh Bharali, Fredrik Larsson, Ralf Jänicke. 2022-02-21. Phase-field fracture irreversibility using the slack variable approach. https://arxiv.org/abs/2202.10040

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