Articles | Volume 13, issue 5
https://doi.org/10.5194/se-13-901-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/se-13-901-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
16 May 2022
Research article |
| 16 May 2022
| 16 May 2022
Failure mode transition in Opalinus Clay: a hydro-mechanical and microstructural perspective
Lisa Winhausen
CORRESPONDING AUTHOR
Department of Engineering Geology and Hydrogeology, RWTH Aachen
University, Lochnerstraße 4–20, 52064 Aachen, Germany
Kavan Khaledi
Department of Engineering Geology and Hydrogeology, RWTH Aachen
University, Lochnerstraße 4–20, 52064 Aachen, Germany
Mohammadreza Jalali
Department of Engineering Geology and Hydrogeology, RWTH Aachen
University, Lochnerstraße 4–20, 52064 Aachen, Germany
Janos L. Urai
Institute of Tectonics and Geodynamics, RWTH Aachen University,
Lochnerstraße 4–20, 52064 Aachen, Germany
Florian Amann
Department of Engineering Geology and Hydrogeology, RWTH Aachen
University, Lochnerstraße 4–20, 52064 Aachen, Germany
Fraunhofer IEG, Fraunhofer Research Institution for Energy
Infrastructures and Geothermal Systems, Kockerellstraße 17, 52062
Aachen, Germany
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Short summary
Triaxial compression tests at different effective stresses allow for analysing the deformation behaviour of Opalinus Clay, the potential host rock for nuclear waste in Switzerland. We conducted microstructural investigations of the deformed samples to relate the bulk hydro-mechanical behaviour to the processes on the microscale. Results show a transition from brittle- to more ductile-dominated deformation. We propose a non-linear failure envelop associated with the failure mode transition.
Triaxial compression tests at different effective stresses allow for analysing the deformation...
