Influence of deviatoric stress dependent stiffness on settlement trough width in 2D and 3D finite element modelling of tunnelling
NGM 2016, 17th Nordic Geotechnical Meeting, Challenges in Nordic Geotechnic, Reykjavik, ISLANDE, 25-/05/2016 - 28/05/2016 Finite element simulations of the construction of shallow tunnels tend to provide poor predictions of the settlements induced at the surface. More precisely, the settlement troug...
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ftuniveiffel:oai:HAL:hal-01472769v1 2023-09-05T13:20:38+02:00 Influence of deviatoric stress dependent stiffness on settlement trough width in 2D and 3D finite element modelling of tunnelling Gilleron, Nicolas Bourgeois, Emmanuel Saitta, Adrien EGIS Laboratoire Instrumentation, Simulation et Informatique Scientifique (IFSTTAR/COSYS/LISIS) Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Communauté Université Paris-Est Reykjavik, Iceland 2016-05-25 https://hal.science/hal-01472769 en eng HAL CCSD hal-01472769 https://hal.science/hal-01472769 NGM 2016, 17th Nordic Geotechnical Meeting, Challenges in Nordic Geotechnic https://hal.science/hal-01472769 NGM 2016, 17th Nordic Geotechnical Meeting, Challenges in Nordic Geotechnic, May 2016, Reykjavik, Iceland. 10p METHODE DES ELEMENTS FINIS TUNNEL TASSEMENT CESAR LCPC (LOGICIEL) [SPI.MECA]Engineering Sciences [physics]/Mechanics [physics.med-ph] info:eu-repo/semantics/conferenceObject Conference papers 2016 ftuniveiffel 2023-08-12T21:31:12Z NGM 2016, 17th Nordic Geotechnical Meeting, Challenges in Nordic Geotechnic, Reykjavik, ISLANDE, 25-/05/2016 - 28/05/2016 Finite element simulations of the construction of shallow tunnels tend to provide poor predictions of the settlements induced at the surface. More precisely, the settlement trough width is generally overestimated by numerical simulations. Many parameters have an influence on the numerical results. In this paper, attention is focused on the constitutive law. Two classic methods of settlement predictions are introduced; a plane strain simulation with the load reduction method and a three dimensional model of conventional tunnelling with numerous excavation steps. After showing some particularity of stress state in soil in the case of a shallow tunnel, we develop a dedicated non-linear elastic law concentrating on the decrease of soil stiffness with increase of deviatoric stress. Indeed an increase of this stress invariant during excavation associated with a stability of the mean effective stress have been shown in the vicinity of the tunnel section especially for 3D modelling. The proposed formulation leads to an initial stiffness that does not depend on depth, which allows testing only the influence of the deviatoric stress variations, a feature which is generally renowned to have a significant influence on the settlement trough width. The influence of the differences between stress paths in the two dimensional and three dimensional simulations is precisely discussed as well as the determination of the stress relaxation factor in 2D modelling. Finally, it appears that, despite the differences in the redistribution of stresses, using a model in which stiffness decreases as the deviatoric stress increases does not make it possible to improve the prediction of settlements both in 2D or 3D. Les simulations par éléments finis du creusement des tunnels peu profonds tendent à donner de mauvaises prédictions des tassements en surface. La largeur de la cuvette de tassement est généralement ... Conference Object Iceland Islande HAL Univ-Eiffel (Université Gustave Eiffel) |
institution |
Open Polar |
collection |
HAL Univ-Eiffel (Université Gustave Eiffel) |
op_collection_id |
ftuniveiffel |
language |
English |
topic |
METHODE DES ELEMENTS FINIS TUNNEL TASSEMENT CESAR LCPC (LOGICIEL) [SPI.MECA]Engineering Sciences [physics]/Mechanics [physics.med-ph] |
spellingShingle |
METHODE DES ELEMENTS FINIS TUNNEL TASSEMENT CESAR LCPC (LOGICIEL) [SPI.MECA]Engineering Sciences [physics]/Mechanics [physics.med-ph] Gilleron, Nicolas Bourgeois, Emmanuel Saitta, Adrien Influence of deviatoric stress dependent stiffness on settlement trough width in 2D and 3D finite element modelling of tunnelling |
topic_facet |
METHODE DES ELEMENTS FINIS TUNNEL TASSEMENT CESAR LCPC (LOGICIEL) [SPI.MECA]Engineering Sciences [physics]/Mechanics [physics.med-ph] |
description |
NGM 2016, 17th Nordic Geotechnical Meeting, Challenges in Nordic Geotechnic, Reykjavik, ISLANDE, 25-/05/2016 - 28/05/2016 Finite element simulations of the construction of shallow tunnels tend to provide poor predictions of the settlements induced at the surface. More precisely, the settlement trough width is generally overestimated by numerical simulations. Many parameters have an influence on the numerical results. In this paper, attention is focused on the constitutive law. Two classic methods of settlement predictions are introduced; a plane strain simulation with the load reduction method and a three dimensional model of conventional tunnelling with numerous excavation steps. After showing some particularity of stress state in soil in the case of a shallow tunnel, we develop a dedicated non-linear elastic law concentrating on the decrease of soil stiffness with increase of deviatoric stress. Indeed an increase of this stress invariant during excavation associated with a stability of the mean effective stress have been shown in the vicinity of the tunnel section especially for 3D modelling. The proposed formulation leads to an initial stiffness that does not depend on depth, which allows testing only the influence of the deviatoric stress variations, a feature which is generally renowned to have a significant influence on the settlement trough width. The influence of the differences between stress paths in the two dimensional and three dimensional simulations is precisely discussed as well as the determination of the stress relaxation factor in 2D modelling. Finally, it appears that, despite the differences in the redistribution of stresses, using a model in which stiffness decreases as the deviatoric stress increases does not make it possible to improve the prediction of settlements both in 2D or 3D. Les simulations par éléments finis du creusement des tunnels peu profonds tendent à donner de mauvaises prédictions des tassements en surface. La largeur de la cuvette de tassement est généralement ... |
author2 |
EGIS Laboratoire Instrumentation, Simulation et Informatique Scientifique (IFSTTAR/COSYS/LISIS) Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Communauté Université Paris-Est |
format |
Conference Object |
author |
Gilleron, Nicolas Bourgeois, Emmanuel Saitta, Adrien |
author_facet |
Gilleron, Nicolas Bourgeois, Emmanuel Saitta, Adrien |
author_sort |
Gilleron, Nicolas |
title |
Influence of deviatoric stress dependent stiffness on settlement trough width in 2D and 3D finite element modelling of tunnelling |
title_short |
Influence of deviatoric stress dependent stiffness on settlement trough width in 2D and 3D finite element modelling of tunnelling |
title_full |
Influence of deviatoric stress dependent stiffness on settlement trough width in 2D and 3D finite element modelling of tunnelling |
title_fullStr |
Influence of deviatoric stress dependent stiffness on settlement trough width in 2D and 3D finite element modelling of tunnelling |
title_full_unstemmed |
Influence of deviatoric stress dependent stiffness on settlement trough width in 2D and 3D finite element modelling of tunnelling |
title_sort |
influence of deviatoric stress dependent stiffness on settlement trough width in 2d and 3d finite element modelling of tunnelling |
publisher |
HAL CCSD |
publishDate |
2016 |
url |
https://hal.science/hal-01472769 |
op_coverage |
Reykjavik, Iceland |
genre |
Iceland Islande |
genre_facet |
Iceland Islande |
op_source |
NGM 2016, 17th Nordic Geotechnical Meeting, Challenges in Nordic Geotechnic https://hal.science/hal-01472769 NGM 2016, 17th Nordic Geotechnical Meeting, Challenges in Nordic Geotechnic, May 2016, Reykjavik, Iceland. 10p |
op_relation |
hal-01472769 https://hal.science/hal-01472769 |
_version_ |
1776201279317475328 |