Evaluation of the CRREL Permafrost Tunnel
The Permafrost Tunnel was excavated in frozen silt and consists of a 110-m-long horizontal adit and a 45-m-long winze that extends down to the underlying gravel. Some change has occurred since the excavation was conducted in the mid-1960s, so a team was assembled in the spring of 2006 to assess thes...
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ftdtic:ADA485745 2023-05-15T16:37:11+02:00 Evaluation of the CRREL Permafrost Tunnel Bjella, Kevin Tantillo, Thomas Weale, Jason Lever, James ENGINEER RESEARCH AND DEVELOPMENT CENTER HANOVER NH COLD REGIONS RESEARCH AND ENGINEERING LAB 2008-08 text/html http://www.dtic.mil/docs/citations/ADA485745 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA485745 en eng http://www.dtic.mil/docs/citations/ADA485745 Approved for public release; distribution is unlimited. DTIC Snow Ice and Permafrost Civil Engineering *PERMAFROST *TUNNELS FREEZING STRUCTURAL INTEGRITY EXCAVATION SILT SOILS DEFORMATION CREEP Text 2008 ftdtic 2016-02-22T16:26:32Z The Permafrost Tunnel was excavated in frozen silt and consists of a 110-m-long horizontal adit and a 45-m-long winze that extends down to the underlying gravel. Some change has occurred since the excavation was conducted in the mid-1960s, so a team was assembled in the spring of 2006 to assess these changes. Frozen silt deformation was noted in the rear of the adit, and a roof fall of the gravel layer was noted in the room at the bottom of the winze. Both of these were found to be attributable to thermal forcing events and the raising of the overall facility temperature to near-freezing temperatures. Sublimation was also noted throughout the tunnel, but this does not pose a problem for the structural integrity of the facility. The team recommends that the facility temperature be lowered to approximately -5 C, which will decrease creep rates and the weakening of lithologic bonds between soil units. Overall, the facility is safe for continued use by researchers and others. The original document contains color images. Text Ice permafrost Defense Technical Information Center: DTIC Technical Reports database |
institution |
Open Polar |
collection |
Defense Technical Information Center: DTIC Technical Reports database |
op_collection_id |
ftdtic |
language |
English |
topic |
Snow Ice and Permafrost Civil Engineering *PERMAFROST *TUNNELS FREEZING STRUCTURAL INTEGRITY EXCAVATION SILT SOILS DEFORMATION CREEP |
spellingShingle |
Snow Ice and Permafrost Civil Engineering *PERMAFROST *TUNNELS FREEZING STRUCTURAL INTEGRITY EXCAVATION SILT SOILS DEFORMATION CREEP Bjella, Kevin Tantillo, Thomas Weale, Jason Lever, James Evaluation of the CRREL Permafrost Tunnel |
topic_facet |
Snow Ice and Permafrost Civil Engineering *PERMAFROST *TUNNELS FREEZING STRUCTURAL INTEGRITY EXCAVATION SILT SOILS DEFORMATION CREEP |
description |
The Permafrost Tunnel was excavated in frozen silt and consists of a 110-m-long horizontal adit and a 45-m-long winze that extends down to the underlying gravel. Some change has occurred since the excavation was conducted in the mid-1960s, so a team was assembled in the spring of 2006 to assess these changes. Frozen silt deformation was noted in the rear of the adit, and a roof fall of the gravel layer was noted in the room at the bottom of the winze. Both of these were found to be attributable to thermal forcing events and the raising of the overall facility temperature to near-freezing temperatures. Sublimation was also noted throughout the tunnel, but this does not pose a problem for the structural integrity of the facility. The team recommends that the facility temperature be lowered to approximately -5 C, which will decrease creep rates and the weakening of lithologic bonds between soil units. Overall, the facility is safe for continued use by researchers and others. The original document contains color images. |
author2 |
ENGINEER RESEARCH AND DEVELOPMENT CENTER HANOVER NH COLD REGIONS RESEARCH AND ENGINEERING LAB |
format |
Text |
author |
Bjella, Kevin Tantillo, Thomas Weale, Jason Lever, James |
author_facet |
Bjella, Kevin Tantillo, Thomas Weale, Jason Lever, James |
author_sort |
Bjella, Kevin |
title |
Evaluation of the CRREL Permafrost Tunnel |
title_short |
Evaluation of the CRREL Permafrost Tunnel |
title_full |
Evaluation of the CRREL Permafrost Tunnel |
title_fullStr |
Evaluation of the CRREL Permafrost Tunnel |
title_full_unstemmed |
Evaluation of the CRREL Permafrost Tunnel |
title_sort |
evaluation of the crrel permafrost tunnel |
publishDate |
2008 |
url |
http://www.dtic.mil/docs/citations/ADA485745 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA485745 |
genre |
Ice permafrost |
genre_facet |
Ice permafrost |
op_source |
DTIC |
op_relation |
http://www.dtic.mil/docs/citations/ADA485745 |
op_rights |
Approved for public release; distribution is unlimited. |
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1766027480779456512 |