CREEP OF ICE AT LOW STRESSES.
Low stress creep measurements were made on commercial ice and small-grained glacier ice in the temperature range from -1.3 to -18.9C at stresses down to about 10,000 dynes/sq. cm. The uniaxial stresses and strain rates were reduced to shear stresses and shear strain rates by respectively dividing an...
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ftdtic:AD0653135 2023-05-15T16:37:09+02:00 CREEP OF ICE AT LOW STRESSES. Butkovich,T. R. Landauer,J. K. SNOW ICE AND PERMAFROST RESEARCH ESTABLISHMENT WILMETTE ILL 1960-08 text/html http://www.dtic.mil/docs/citations/AD0653135 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=AD0653135 en eng http://www.dtic.mil/docs/citations/AD0653135 APPROVED FOR PUBLIC RELEASE DTIC AND NTIS Snow Ice and Permafrost (*ICE CREEP) STRESSES GLACIERS SHEAR STRESSES MEASUREMENT STRAIN(MECHANICS) Text 1960 ftdtic 2016-02-18T20:09:47Z Low stress creep measurements were made on commercial ice and small-grained glacier ice in the temperature range from -1.3 to -18.9C at stresses down to about 10,000 dynes/sq. cm. The uniaxial stresses and strain rates were reduced to shear stresses and shear strain rates by respectively dividing and multiplying the former by the square root of 3. The log shear strain rate vs log shear stress curves was essentially linear for the low-stress creep measurements. Assuming a linear flow law for low-stress creep, activation energies for creep of about 14,300 cal/mole were determined. It can also be seen that the smaller-grained ice has a higher viscosity coefficient. The observed activation energy for creep of ice is probably that for self-diffusion. Although lacking a concrete deformation mechanism, the rate process theory, which leads to a hyperbolic sine stress dependence, seems to best describe the experimental results. (Author) 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 (*ICE CREEP) STRESSES GLACIERS SHEAR STRESSES MEASUREMENT STRAIN(MECHANICS) |
spellingShingle |
Snow Ice and Permafrost (*ICE CREEP) STRESSES GLACIERS SHEAR STRESSES MEASUREMENT STRAIN(MECHANICS) Butkovich,T. R. Landauer,J. K. CREEP OF ICE AT LOW STRESSES. |
topic_facet |
Snow Ice and Permafrost (*ICE CREEP) STRESSES GLACIERS SHEAR STRESSES MEASUREMENT STRAIN(MECHANICS) |
description |
Low stress creep measurements were made on commercial ice and small-grained glacier ice in the temperature range from -1.3 to -18.9C at stresses down to about 10,000 dynes/sq. cm. The uniaxial stresses and strain rates were reduced to shear stresses and shear strain rates by respectively dividing and multiplying the former by the square root of 3. The log shear strain rate vs log shear stress curves was essentially linear for the low-stress creep measurements. Assuming a linear flow law for low-stress creep, activation energies for creep of about 14,300 cal/mole were determined. It can also be seen that the smaller-grained ice has a higher viscosity coefficient. The observed activation energy for creep of ice is probably that for self-diffusion. Although lacking a concrete deformation mechanism, the rate process theory, which leads to a hyperbolic sine stress dependence, seems to best describe the experimental results. (Author) |
author2 |
SNOW ICE AND PERMAFROST RESEARCH ESTABLISHMENT WILMETTE ILL |
format |
Text |
author |
Butkovich,T. R. Landauer,J. K. |
author_facet |
Butkovich,T. R. Landauer,J. K. |
author_sort |
Butkovich,T. R. |
title |
CREEP OF ICE AT LOW STRESSES. |
title_short |
CREEP OF ICE AT LOW STRESSES. |
title_full |
CREEP OF ICE AT LOW STRESSES. |
title_fullStr |
CREEP OF ICE AT LOW STRESSES. |
title_full_unstemmed |
CREEP OF ICE AT LOW STRESSES. |
title_sort |
creep of ice at low stresses. |
publishDate |
1960 |
url |
http://www.dtic.mil/docs/citations/AD0653135 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=AD0653135 |
genre |
Ice permafrost |
genre_facet |
Ice permafrost |
op_source |
DTIC AND NTIS |
op_relation |
http://www.dtic.mil/docs/citations/AD0653135 |
op_rights |
APPROVED FOR PUBLIC RELEASE |
_version_ |
1766027446758408192 |