Modelling of cryogenic processes in permafrost and seasonally frozen soils
This paper investigates the thermo-hydro-mechanical (THM) behaviour of soils subjected to seasonal temperature variations in both permafrost and seasonally frozen conditions. Numerical modelling of soil freezing and ice segregation processes is presented, and compared against small-scale physical mo...
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Thomas Telford Ltd.
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Online Access: | http://dx.doi.org/10.1680/geot.2009.59.3.173 https://www.icevirtuallibrary.com/doi/pdf/10.1680/geot.2009.59.3.173 |
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crtelford:10.1680/geot.2009.59.3.173 2024-06-23T07:53:37+00:00 Modelling of cryogenic processes in permafrost and seasonally frozen soils Thomas, H. R. Cleall, P. Li, Y.-C. Harris, C. Kern-Luetschg, M. 2009 http://dx.doi.org/10.1680/geot.2009.59.3.173 https://www.icevirtuallibrary.com/doi/pdf/10.1680/geot.2009.59.3.173 en eng Thomas Telford Ltd. Géotechnique volume 59, issue 3, page 173-184 ISSN 0016-8505 1751-7656 journal-article 2009 crtelford https://doi.org/10.1680/geot.2009.59.3.173 2024-06-13T04:19:04Z This paper investigates the thermo-hydro-mechanical (THM) behaviour of soils subjected to seasonal temperature variations in both permafrost and seasonally frozen conditions. Numerical modelling of soil freezing and ice segregation processes is presented, and compared against small-scale physical modelling experiments. The coupled THM model presented, which is solved by way of a transient finite element approach, considers a number of processes, including conduction, convection, phase change, the movement of moisture due to cryogenic suctions, and the development of ice lenses. Two seasonal freezing scenarios are considered: (a) for soils with no permafrost, where freezing is from the surface downward (one-sided freezing); and (b) for soils underlain by permafrost, where large thermal gradients in the uppermost permafrost layer can cause active layer freezing in two directions, from the permafrost table upwards and from the ground surface downwards (two-sided freezing). In the case of one-sided freezing, ice lens formation occurs as the freezing front advances downwards from the surface, and is limited by water supply. However, during two-sided freezing, ice segregation takes place in a closed system, with ice lenses accumulating at the base of the active layer and near the ground surface, leaving an intervening ice-poor zone. Numerical modelling is able to represent the development of both the thermal field and ice segregation observed in the physical models. The significance of this contrasting ground ice distribution is considered in the context of thaw-related slow mass movement processes (solifluction). Article in Journal/Newspaper Ice permafrost ICE Virtual Library (ICE Publishing) Géotechnique 59 3 173 184 |
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Open Polar |
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ICE Virtual Library (ICE Publishing) |
op_collection_id |
crtelford |
language |
English |
description |
This paper investigates the thermo-hydro-mechanical (THM) behaviour of soils subjected to seasonal temperature variations in both permafrost and seasonally frozen conditions. Numerical modelling of soil freezing and ice segregation processes is presented, and compared against small-scale physical modelling experiments. The coupled THM model presented, which is solved by way of a transient finite element approach, considers a number of processes, including conduction, convection, phase change, the movement of moisture due to cryogenic suctions, and the development of ice lenses. Two seasonal freezing scenarios are considered: (a) for soils with no permafrost, where freezing is from the surface downward (one-sided freezing); and (b) for soils underlain by permafrost, where large thermal gradients in the uppermost permafrost layer can cause active layer freezing in two directions, from the permafrost table upwards and from the ground surface downwards (two-sided freezing). In the case of one-sided freezing, ice lens formation occurs as the freezing front advances downwards from the surface, and is limited by water supply. However, during two-sided freezing, ice segregation takes place in a closed system, with ice lenses accumulating at the base of the active layer and near the ground surface, leaving an intervening ice-poor zone. Numerical modelling is able to represent the development of both the thermal field and ice segregation observed in the physical models. The significance of this contrasting ground ice distribution is considered in the context of thaw-related slow mass movement processes (solifluction). |
format |
Article in Journal/Newspaper |
author |
Thomas, H. R. Cleall, P. Li, Y.-C. Harris, C. Kern-Luetschg, M. |
spellingShingle |
Thomas, H. R. Cleall, P. Li, Y.-C. Harris, C. Kern-Luetschg, M. Modelling of cryogenic processes in permafrost and seasonally frozen soils |
author_facet |
Thomas, H. R. Cleall, P. Li, Y.-C. Harris, C. Kern-Luetschg, M. |
author_sort |
Thomas, H. R. |
title |
Modelling of cryogenic processes in permafrost and seasonally frozen soils |
title_short |
Modelling of cryogenic processes in permafrost and seasonally frozen soils |
title_full |
Modelling of cryogenic processes in permafrost and seasonally frozen soils |
title_fullStr |
Modelling of cryogenic processes in permafrost and seasonally frozen soils |
title_full_unstemmed |
Modelling of cryogenic processes in permafrost and seasonally frozen soils |
title_sort |
modelling of cryogenic processes in permafrost and seasonally frozen soils |
publisher |
Thomas Telford Ltd. |
publishDate |
2009 |
url |
http://dx.doi.org/10.1680/geot.2009.59.3.173 https://www.icevirtuallibrary.com/doi/pdf/10.1680/geot.2009.59.3.173 |
genre |
Ice permafrost |
genre_facet |
Ice permafrost |
op_source |
Géotechnique volume 59, issue 3, page 173-184 ISSN 0016-8505 1751-7656 |
op_doi |
https://doi.org/10.1680/geot.2009.59.3.173 |
container_title |
Géotechnique |
container_volume |
59 |
container_issue |
3 |
container_start_page |
173 |
op_container_end_page |
184 |
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1802645355563581440 |