Articles | Volume 12, issue 9
https://doi.org/10.5194/se-12-2109-2021
© Author(s) 2021. 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-12-2109-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
23 Sep 2021
Research article |
| 23 Sep 2021
| 23 Sep 2021
Micromechanisms leading to shear failure of Opalinus Clay in a triaxial test: a high-resolution BIB–SEM study
Lisa Winhausen
CORRESPONDING AUTHOR
Department of Engineering Geology and Hydrogeology, RWTH Aachen
University, 52064 Aachen, Germany
Jop Klaver
MaP – Microstructures and Pores GmbH, Lochnerstraße 4–20, 52064
Aachen, Germany
Joyce Schmatz
MaP – Microstructures and Pores GmbH, Lochnerstraße 4–20, 52064
Aachen, Germany
Guillaume Desbois
Institute of Structural Geology, Tectonics and Geomechanics, RWTH
Aachen University, 52064 Aachen, Germany
Janos L. Urai
Institute of Tectonics and Geodynamics, RWTH Aachen University,
52064 Aachen, Germany
Florian Amann
Department of Engineering Geology and Hydrogeology, RWTH Aachen
University, 52064 Aachen, Germany
Christophe Nussbaum
Federal Office of Topography Swisstopo, Route de la Gare 63, 2882
St.-Ursanne, Switzerland
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Short summary
An experimentally deformed sample of Opalinus Clay (OPA), which is being considered as host rock for nuclear waste in Switzerland, was studied by electron microscopy to image deformation microstructures. Deformation localised by forming micrometre-thick fractures. Deformation zones show dilatant micro-cracking, granular flow and bending grains, and pore collapse. Our model, with three different stages of damage accumulation, illustrates microstructural deformation in a compressed OPA sample.
An experimentally deformed sample of Opalinus Clay (OPA), which is being considered as host rock...
