Paper contribution

Artificial Fracture Generation and Surface Roughness Quantification in Brittle Rocks

Tégawendé Nikiema; Nicolas Gonze; Fanny Descamps; Jean-Pierre Tshibangu

Proceedings
EUROCK 2026
Pages
473-478
Submitted
28 January 2026
Accepted
15 June 2026
Published
12 August 2026

Summary

Abstract

Understanding the mechanical behaviour of rock masses is essential for the design and stability of infrastructures such as tunnels, slopes, and underground storage facilities. At these scales, discontinuities largely govern the global response of the rock mass. To investigate their behaviour, researchers typically adopt two approaches: working on natural fractures or on artificial ones. Natural fractures provide realistic conditions but pose significant challenges, both in terms of sampling and reproducibility. Artificial fractures, on the other hand, offer better control. They can be either molded from natural fracture surfaces, preserving geometry but losing the original rock behaviour, or generated directly in the laboratory, which risks damaging the specimen. In this study, we focus on producing laboratory-induced fractures under controlled conditions to maintain the integrity of the rock. Fracture initiation and propagation depend on the loading conditions, the mechanical properties, and the mineralogical composition of the rock. In this work, aiming to produce fractures that preserve the morphology of natural rock splinters, an original methodology is developed to generate tensile fractures in rock samples by using a 285 kN compression frame equipped with a blades-jaw system. This setup was tested on prismatic specimens of Soignies Limestone and Vosges Sandstone. These two rocks exhibit brittle behaviour under atmospheric conditions but differ markedly in porosity, stiffness, and strength (high to moderate), leading to distinct fracture patterns. Optical profilometry is used to accurately characterize the geometry of fracture surfaces. Statistical roughness parameters and the Joint Roughness Coefficient (JRC) were used to quantify and compare the surface roughness of both rocks and address the variability of laboratory generated fractures. The methodology will play a key role for future work that will focus on linking joint geometry with the mechanical response of fractured rocks under controlled loading conditions.

Contributors

Authors

  1. Tégawendé Nikiema University of Mons/ Faculty of engineeing, Belgium ORCID 0000-0003-2079-2087
  2. Nicolas Gonze University of Mons/ Faculty of engineeing, Belgium
  3. Fanny Descamps University of Mons/ Faculty of engineeing, Belgium
  4. Jean-Pierre Tshibangu University of Mons/ Faculty of engineeing, Belgium

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References

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