the idea

The mechanical and hydraulic behaviour of rock mass is governed by the existing fracture network. Fractures host the deformation and govern fluid flow. Therefore, it is a logical move to introduce a software that can simulate the evolution of the fracture network. The evolution of the fracture network is modelled in roxol by dedicated employment of fracture mechanics principles. This ensures that the input parameters to the code have a physical meaning and can be determined in the laboratory. Development of roxol started with this idea in mind in 2010 and is available for studies now. Initially, both the mathematical but also geomechanical framework had to be developed. roxol consequently is based on an open software architecture and latest software development standards. This ensures easy and safe extension of the code in upcoming developments, while offering backward compatibility of projects.

specifications

  • semi-coupled HFM (hydro-fracture-mechanical) simulations
  • orthotropic rock deformation
  • predefined fractures
  • statistically generated fracture networks
  • fracture initiation by different models
  • fracture propagation by different models
  • fracture coalescence
  • various predefined excavations
  • various static and sequential boundary conditions
  • basic excavation support features
  • static and non-static fluid pressure on fractures
  • seamless workflows
  • fully integrated graphical user experience
  • open development architecture
  • latest X-FEM standards

development

Development of roxol started in 2010 and is used in our consultancy now. In parallel general functionality extension is ongoing. Also the performance and stability of the system is constantly improved.
The development of roxol was supported by the Federal State of Brandenburg, Germany, the European Union (European Fund for Regional Development, program 'Investment to future'), the German Ministry for Environment BMU, and the German Ministry of Economics BMWi.

Mode I fracture propagation

A single fracture in a plate subject to tension propagates through a homogeneous medium (Young's modulus 70GPa, Poisson's ration 0.27). The analytical solution for the critical stress and the simulations are in excellent agreement (Mode I fracture toughness K = 1MPa√m). Two different meshes are tested; the graded mesh shows the even better results.

Mode II fracture propagation

A single fracture in a plate subject to compression propagates through a homogeneous medium (Young's modulus 70GPa, Poisson's ration 0.27). The analytical solution for the critical stress and the simulations are in excellent agreement (Mode II fracture toughness K = 1MPa√m). Two different meshes are tested.

the premium application program

roxol is not available for purchase currently. However, we have introduced the roxol premium application program, which gives you the possibility to receive a personal copy of the code. Within the roxol premium application program the geomecon experts will work together with you on a predefined topic. For that purpose you may contact us with a project proposal to receive a dedicated license. Ask for the terms of the roxol premium application program by contacting us.


send request to solutions@geomecon.de
 
 

examples of publications and talks

  • Rabbel O, Mair K, Galland O, Grühser C, Meier T. 2020. Numerical Modeling of Fracture Network Evolution in Organic‐Rich Shale With Rapid Internal Fluid Generation. JGR Solid Earth, Volume 125, Issue 7.
  • Nardini L, Rybacki E, Krause M, Morales LFG, Dresen G. 2020. Control of the geometric arrangement of material heterogeneities on strain localization at the brittle-to-ductile transition in experimentally deformed carbonate rocks. Journal of Structural Geology Volume 135.
  • Backers T, Gruehser C, Meier T and Dresen G. 2012. Fracture Pattern of Borehole Breakouts in Shale - Comparison of Physical and Numerical Experiments. EAGE. Copenhagen, Denmark
  • Mischo H and Backers T. 2012. Analysis of fracture coalescence by fracture mechanics simulation. EUROCK, Stockholm, Sweden
  • Backers T and Stephansson O. 2011. Examples of application of fracture mechanical simulations in Geomechanics. 18. Tagung fuer Ingenieurgeologie und Forum Junge Ingenieurgeologen, Berlin
  • Byfut A, Backers T, Schroeder A and Carstensen C. 2009. Appliance of the Extended Finite Element Method in Geomechanics. 71st EAGE Conference and Exhibition 2009, Amsterdam, The Netherlands

references

We have conducted a selection of different projects delivering solutions to our customers using roxol, e.g.

  • Central European Petroleum, Germany
  • GeoEnergy Suisse, Switzerland
  • nagra, Switzerland
  • Ruhr University Bochum, Germany
  • Swedish Radiation Safety Authority SSM, Sweden
  • Helmholtz Centre Potsdam GFZ, Germany
  • University of Oslo, Norway

trademark

roxol and the roxol logo are registered trademarks of geomecon GmbH.