A numerical study on the coupled hydro-mechanical behaviour of compacted bentonite

Understanding the mechanical behaviour of compacted bentonite upon re-saturation is of outmost importance in most designs of nuclear waste disposal repositories. The behaviour of bentonite is characterized by its stress-path dependency and it is typically interpreted on the basis of its microstructu...

Full description

Bibliographic Details
Main Authors: Bosch Jose A., Ferrari Alessio, Laloui Lyesse
Format: Article
Language:English
Published: EDP Sciences 2020-01-01
Series:E3S Web of Conferences
Online Access:https://www.e3s-conferences.org/articles/e3sconf/pdf/2020/65/e3sconf_icegt2020_10001.pdf
_version_ 1818441687623532544
author Bosch Jose A.
Ferrari Alessio
Laloui Lyesse
author_facet Bosch Jose A.
Ferrari Alessio
Laloui Lyesse
author_sort Bosch Jose A.
collection DOAJ
description Understanding the mechanical behaviour of compacted bentonite upon re-saturation is of outmost importance in most designs of nuclear waste disposal repositories. The behaviour of bentonite is characterized by its stress-path dependency and it is typically interpreted on the basis of its microstructural interactions. Up to now, effective stress-based models have had limited success in reproducing consistently the main responses. Here a recently proposed model for the modelling of volumetric behaviour of compacted bentonites is extended to triaxial stress states. The model is formulated using a conventional effective stress expression and the degree of saturation. Because these two variables are directly related to the water retention, a suitable formulation for bentonites is used. The resulting equations are characterised by a high degree of hydro- mechanical couplings and a low number of material parameters, which can be obtained on the basis of well- established laboratory procedures. In order to demonstrate its capabilities, the model is used to simulate the behaviour of MX-80 bentonite for several stress paths under oedometric conditions. The emphasis is put on the process of parameter determination. The predictive capabilities of the model are also highlighted.
first_indexed 2024-12-14T18:32:13Z
format Article
id doaj.art-5b80f600299f47358aac3ad017b38b1b
institution Directory Open Access Journal
issn 2267-1242
language English
last_indexed 2024-12-14T18:32:13Z
publishDate 2020-01-01
publisher EDP Sciences
record_format Article
series E3S Web of Conferences
spelling doaj.art-5b80f600299f47358aac3ad017b38b1b2022-12-21T22:51:45ZengEDP SciencesE3S Web of Conferences2267-12422020-01-012051000110.1051/e3sconf/202020510001e3sconf_icegt2020_10001A numerical study on the coupled hydro-mechanical behaviour of compacted bentoniteBosch Jose A.0Ferrari Alessio1Laloui Lyesse2Swiss Federal Institute of Technology in LausanneSwiss Federal Institute of Technology in LausanneSwiss Federal Institute of Technology in LausanneUnderstanding the mechanical behaviour of compacted bentonite upon re-saturation is of outmost importance in most designs of nuclear waste disposal repositories. The behaviour of bentonite is characterized by its stress-path dependency and it is typically interpreted on the basis of its microstructural interactions. Up to now, effective stress-based models have had limited success in reproducing consistently the main responses. Here a recently proposed model for the modelling of volumetric behaviour of compacted bentonites is extended to triaxial stress states. The model is formulated using a conventional effective stress expression and the degree of saturation. Because these two variables are directly related to the water retention, a suitable formulation for bentonites is used. The resulting equations are characterised by a high degree of hydro- mechanical couplings and a low number of material parameters, which can be obtained on the basis of well- established laboratory procedures. In order to demonstrate its capabilities, the model is used to simulate the behaviour of MX-80 bentonite for several stress paths under oedometric conditions. The emphasis is put on the process of parameter determination. The predictive capabilities of the model are also highlighted.https://www.e3s-conferences.org/articles/e3sconf/pdf/2020/65/e3sconf_icegt2020_10001.pdf
spellingShingle Bosch Jose A.
Ferrari Alessio
Laloui Lyesse
A numerical study on the coupled hydro-mechanical behaviour of compacted bentonite
E3S Web of Conferences
title A numerical study on the coupled hydro-mechanical behaviour of compacted bentonite
title_full A numerical study on the coupled hydro-mechanical behaviour of compacted bentonite
title_fullStr A numerical study on the coupled hydro-mechanical behaviour of compacted bentonite
title_full_unstemmed A numerical study on the coupled hydro-mechanical behaviour of compacted bentonite
title_short A numerical study on the coupled hydro-mechanical behaviour of compacted bentonite
title_sort numerical study on the coupled hydro mechanical behaviour of compacted bentonite
url https://www.e3s-conferences.org/articles/e3sconf/pdf/2020/65/e3sconf_icegt2020_10001.pdf
work_keys_str_mv AT boschjosea anumericalstudyonthecoupledhydromechanicalbehaviourofcompactedbentonite
AT ferrarialessio anumericalstudyonthecoupledhydromechanicalbehaviourofcompactedbentonite
AT lalouilyesse anumericalstudyonthecoupledhydromechanicalbehaviourofcompactedbentonite
AT boschjosea numericalstudyonthecoupledhydromechanicalbehaviourofcompactedbentonite
AT ferrarialessio numericalstudyonthecoupledhydromechanicalbehaviourofcompactedbentonite
AT lalouilyesse numericalstudyonthecoupledhydromechanicalbehaviourofcompactedbentonite