Abstract
The geomaterials such as soils and rocks are multiphase porous media with complex structure that is
characterised by heterogeneity and possible anisotropy at various scales. It is obvious that, the heterogeneous
nature of the material is originated by the small-scale properties1
. The microscopic behaviour of rocks is
characterised by the material and morphological (grain shape and size) properties of its components and their
interactions. The accurate reproduction and influence of these microscale characteristics on the material
behaviour and damage at large scale remain a complex issue. This question becomes crucial when investigating
the underground stability during excavation works such as galleries and tunnels 2 3
. In this study, the
microstructure characteristics are embedded in a representative volume element (RVE) 4
. A double-scale
numerical framework, with finite element resolution at both scales (FEM²) and computational homogenisation,
is considered5 6
. The influence of the microstructural characteristics of heterogeneous rocks and the effect of
different inter-granular properties on their macroscopic behaviour, are examined. Additionally, a predictive
strategy which is based on the connection between the failure modes of the RVE and the failure mechanisms of
the macroscale structure is also presented. This study investigates the effect of the microcracking on the
regularised shear banding in a soil specimen during biaxial shear test and the development of the Excavation
Damaged Zone (EDZ) around tunnels. The objective of this work, is to explain the failure mechanisms observed
up to the engineering scale of underground structures through the morphological and material small-scale
characteristics of the RVE.
characterised by heterogeneity and possible anisotropy at various scales. It is obvious that, the heterogeneous
nature of the material is originated by the small-scale properties1
. The microscopic behaviour of rocks is
characterised by the material and morphological (grain shape and size) properties of its components and their
interactions. The accurate reproduction and influence of these microscale characteristics on the material
behaviour and damage at large scale remain a complex issue. This question becomes crucial when investigating
the underground stability during excavation works such as galleries and tunnels 2 3
. In this study, the
microstructure characteristics are embedded in a representative volume element (RVE) 4
. A double-scale
numerical framework, with finite element resolution at both scales (FEM²) and computational homogenisation,
is considered5 6
. The influence of the microstructural characteristics of heterogeneous rocks and the effect of
different inter-granular properties on their macroscopic behaviour, are examined. Additionally, a predictive
strategy which is based on the connection between the failure modes of the RVE and the failure mechanisms of
the macroscale structure is also presented. This study investigates the effect of the microcracking on the
regularised shear banding in a soil specimen during biaxial shear test and the development of the Excavation
Damaged Zone (EDZ) around tunnels. The objective of this work, is to explain the failure mechanisms observed
up to the engineering scale of underground structures through the morphological and material small-scale
characteristics of the RVE.
Original language | English |
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Pages | 3-3 |
Number of pages | 1 |
Publication status | Published - 27 May 2021 |
Event | Séance technique: Les avancées récentes sur la modélisation numérique du comportement des roches - online, online Duration: 27 May 2021 → 27 May 2021 https://www.cfmr-roches.org/manifestations-et-evenements/passees |
Conference
Conference | Séance technique |
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City | online |
Period | 27/05/21 → 27/05/21 |
Internet address |