Paper contribution

Phase-field fracture simulation of the strain rate effect on fracture propagation

Armin Chehreh; Lucas Conrad Witte; Mandy Duda; Tobias Backers

Proceedings
EUROCK 2026
Pages
219-224
Submitted
28 January 2026
Accepted
15 June 2026
Published
12 August 2026

Summary

Abstract

For the spatial and temporal upscaling of results from uniaxial compressive strength tests on rocks, numerical methods are necessary to predict rock behavior under complex geomechanical conditions, as in foundation, slope stability, underground space, and reservoir studies. Correctly estimating the impact of time and size can lead to reduced design risk. Previous studies on phase-field modeling of rocks often employed a single open flaw to simulate fracture initiation, and two to four open flaws to represent fracture propagation and failure. These flaws were generally arranged in a geometrically ordered pattern. However, in natural rock formations, microfractures are predominantly closed and exhibit a more or less random distribution depending on texture. This study used a phase-field approach to simulate brittle fractures in granite containing multiple randomly distributed, closed pre-existing microcracks, employing the principal stress criterion as the driving force in the phase-field evolution equation. This study focuses on analyzing the sensitivity of the model to crack density and phase-field parameters. The effect of strain rate was investigated, and phase-field parameters were calibrated accordingly. To demonstrate the accuracy of the presented approach, numerical simulations are compared with experimentally obtained results, showing that the approach is capable of temporal and spatial upscaling when microstructural features are considered.

Contributors

Authors

  1. Armin Chehreh Ruhr University Bochum, Germany
  2. Lucas Conrad Witte Ruhr University Bochum, Germany
  3. Mandy Duda Ruhr University Bochum, Germany
  4. Tobias Backers Ruhr University Bochum, Germany

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References

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