PSI - Issue 80

Roman Vodička et al. / Procedia Structural Integrity 80 (2026) 501 – 508 R. Vodicˇka / Structural Integrity Procedia 00 (2025) 000–000

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(a)

(b)

Fig. 5. Distributions of the stress: (a) the norm of deviatoric stress, (b) stress trace in the beam at the instants for g = 0 . 225 , 0 . 625 , 0 . 875 , 0 . 9 , 0 . 95 , 1 . 0mm.

5. Conclusions

The paper presented an outline of a computational model which enables to propagate cracks inside material which exhibit some kind of ductility represented be evolution of plastic deformations. The process of degradation is thus understood as competition between plasticity and phase-field damage. The model thus requires to adjust parameters for either process as they modify degradation processes in materials. This adjustment should be done in comparison to experimental measurements. Though the computational implementation was not described in detail, a few features were mentioned: a stag gered time stepping which provided possibility to describe the solution process variationally. The calculations were performed in an in-house MATLAB code which applies specific algorithms of sequential quadratic programming methods within a finite element approach. While the results are presented only for one example, it is expected that the presented approach will be appropriate also for crack propagation in other calculations.

Acknowledgements

The author acknowledges support by the grants VEGA 1 / 0365 / 25 and VEGA 1 / 0307 / 23.

References

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