EGU25-15632, updated on 15 Mar 2025
https://doi.org/10.5194/egusphere-egu25-15632
EGU General Assembly 2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
Simulation of displacement rate effect on tensile rock failure using a phase-field fracture approach
Hossein Asghari Chehreh, Lucas Witte, Mandy Duda, and Tobias Backers
Hossein Asghari Chehreh et al.
  • Ruhr University, Geoscience , Engineering geology and Rock mechanics, Germany (hachehreh@gmail.com)

The tensile strength of brittle rocks is commonly determined experimentally using the Brazilian test (splitting tensile strength test). For spatial and temporal upscaling of these experimental results, numerical methods are necessary to predict rock behaviour under complex geomechanical conditions such as foundation, slope stability, underground space and reservoirs studies, and to analyse the influence of individual parameters on the outcomes.

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 model 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, spatial distribution, and phase-field parameters. The effect of displacement rate was investigated, and phase-field parameters were calibrated accordingly. To demonstrate the presented approach's accuracy, numerical simulations are compared to experimentally obtained results showing that the approach is in principle capable of temporal and spatial upscaling when microstructural features are considered.

How to cite: Asghari Chehreh, H., Witte, L., Duda, M., and Backers, T.: Simulation of displacement rate effect on tensile rock failure using a phase-field fracture approach, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-15632, https://doi.org/10.5194/egusphere-egu25-15632, 2025.