PSI - Issue 35

S. YaŞayanlar et al. / Procedia Structural Integrity 35 (2022) 18– 24

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Yas¸ayanlar et al. / Structural Integrity Procedia 00 (2021) 000–000

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Fig. 5: Pressure distribution at the mid-section of the specimen obtained by (Left) two-field formulation; (Right) three-field formulation.

5. Conclusion and Outlook

In this work, failure of elastoplastic materials is addressed by means of continuum damage mechanics. Artificial di ff usion of localization band and the treatment of volumetric locking were the major issues which were tackled with in this contribution. Recently proposed LIGD formulation and mixed displacement-pressure (u-p) formulations have been successfully implemented through Abaqus user element subroutines. It is demonstrated that by means of LIGD formulation, artificial widening of the localization band is circumvented and a di ff erent localization band orientation may emerge. In case of incompressible plasticity models, although the global quantities might seem to be satisfactory, the pressure distributions would be wrong. Furthermore, the problematic pressure distribution might be the reason of divergence observed in case of displacement formulation.

Acknowledgements

This work was supported by the Scientific Research Projects O ffi ce of ˙Izmir Institute of Technology (project num ber 2020 ˙IYTE0036), which is gratefully acknowledged.

References

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