Paper contribution

Resolution-induced uncertainty in DEM-predicted brittle damage thresholds in sandstone

Jinci Chen; Elli-Maria Charalampidou; Ali Ozel; James Woodman; Audrey Ougier-Simonin

Proceedings
EUROCK 2026
Pages
645-650
Submitted
30 April 2026
Accepted
15 June 2026
Published
12 August 2026

Summary

Abstract

Brittle damage thresholds predicted by discrete element method (DEM) modelling are informative for interpreting rock failure processes and supporting engineering design. Nonetheless, these predictions are constrained by the model particle resolution. This study investigates whether variations in model particle resolution affect the interpretation of damage thresholds in sandstone subjected to uniaxial compression. A recently developed Subspring Network Breakable Voronoi model was used to simulate uniaxial compression at four different particle resolutions. The results show a systematic dependence of the predicted response on model particle resolution. With increasing resolution, the predicted uniaxial compressive strength, crack initiation, and crack damage thresholds generally increase, while Young’s modulus decreases slightly and Poisson’s ratio shows limited sensitivity. Finer resolutions also produce significantly higher crack counts and denser fracture patterns. Despite these variations, the dominant macroscopic failure mode remains tensile dominated; axial splitting is observed across all resolutions. These findings indicate that model particle resolution influences quantitative interpretations of brittle damage more strongly than qualitative identification of failure modes. Consequently, model particle resolution should not be treated merely as a numerical setting but rather as a source of modelling uncertainty in DEM based rock engineering analyses. An intermediate model particle resolution is considered to provide a practical compromise between computational efficiency and representative failure behaviour.

Contributors

Authors

  1. Jinci Chen Institute of GeoEnergy Engineering, School of Energy, Geoscience, Infrastructure and Society, Heriot-Watt University, Edinburgh, UK; British Geological Survey, Keyworth, Nottingham, UK ORCID 0009-0002-0920-9778
  2. Elli-Maria Charalampidou Institute of GeoEnergy Engineering, School of Energy, Geoscience, Infrastructure and Society, Heriot-Watt University, Edinburgh, UK
  3. Ali Ozel School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, UK
  4. James Woodman Geo-Design Consulting Engineers Ltd, Ringwood, UK
  5. Audrey Ougier-Simonin British Geological Survey, Keyworth, Nottingham, UK

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References

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