Author: Ukichirō Nakaya
Publisher:
ISBN:
Category : Greenland
Languages : en
Pages : 44
Book Description
Experiments were carried out near Thule, Greenland, on the correlation between the physical properties and internal structure of snow. About 150 snow samples obtained to 26 m depth were measured for elastic modulus, air permeability, unconfined compressive strength, static compression and creep. The observed density profile curve deviated from the theoretical curve at a depth of 10 m. and density of 0.52 g/cu cm, a value almost equivalent to the limiting density obtainable by simple mechanical packing. Therefore, further densification must proceed through plastic flow in grains. A similar critical depth was observed in the vertical distribution of Young's modulus. A positive correlation was found between Young's modulus and an adverse correlation between average grain diameter and Young's modulus or density. There were reciprocal correlations between air permeability and density or unconfined compressive strength, and between the number of grains and their average diameters. Kozeny's constant of Greenland snow was obtained from air permeability values and the length of peripheries of cross sections of grains. To demonstrate the change of internal structure of snow due to densification, static compression tests of snow cylinders were conducted, and thin sections of snow texture were compared before and after compression. (Author).
Physical Properties and Internal Structure of Greenland Snow
Author: Ukichirō Nakaya
Publisher:
ISBN:
Category : Greenland
Languages : en
Pages : 44
Book Description
Experiments were carried out near Thule, Greenland, on the correlation between the physical properties and internal structure of snow. About 150 snow samples obtained to 26 m depth were measured for elastic modulus, air permeability, unconfined compressive strength, static compression and creep. The observed density profile curve deviated from the theoretical curve at a depth of 10 m. and density of 0.52 g/cu cm, a value almost equivalent to the limiting density obtainable by simple mechanical packing. Therefore, further densification must proceed through plastic flow in grains. A similar critical depth was observed in the vertical distribution of Young's modulus. A positive correlation was found between Young's modulus and an adverse correlation between average grain diameter and Young's modulus or density. There were reciprocal correlations between air permeability and density or unconfined compressive strength, and between the number of grains and their average diameters. Kozeny's constant of Greenland snow was obtained from air permeability values and the length of peripheries of cross sections of grains. To demonstrate the change of internal structure of snow due to densification, static compression tests of snow cylinders were conducted, and thin sections of snow texture were compared before and after compression. (Author).
Publisher:
ISBN:
Category : Greenland
Languages : en
Pages : 44
Book Description
Experiments were carried out near Thule, Greenland, on the correlation between the physical properties and internal structure of snow. About 150 snow samples obtained to 26 m depth were measured for elastic modulus, air permeability, unconfined compressive strength, static compression and creep. The observed density profile curve deviated from the theoretical curve at a depth of 10 m. and density of 0.52 g/cu cm, a value almost equivalent to the limiting density obtainable by simple mechanical packing. Therefore, further densification must proceed through plastic flow in grains. A similar critical depth was observed in the vertical distribution of Young's modulus. A positive correlation was found between Young's modulus and an adverse correlation between average grain diameter and Young's modulus or density. There were reciprocal correlations between air permeability and density or unconfined compressive strength, and between the number of grains and their average diameters. Kozeny's constant of Greenland snow was obtained from air permeability values and the length of peripheries of cross sections of grains. To demonstrate the change of internal structure of snow due to densification, static compression tests of snow cylinders were conducted, and thin sections of snow texture were compared before and after compression. (Author).
USA CRREL Technical Publications
Author: Cold Regions Research and Engineering Laboratory (U.S.)
Publisher:
ISBN:
Category : Frozen ground
Languages : en
Pages : 386
Book Description
Publisher:
ISBN:
Category : Frozen ground
Languages : en
Pages : 386
Book Description
Research Report - Corps of Engineers, U.S. Army, Cold Regions Research and Engineering Laboratory
Author: Cold Regions Research and Engineering Laboratory (U.S.)
Publisher:
ISBN:
Category : Frozen ground
Languages : en
Pages : 46
Book Description
Publisher:
ISBN:
Category : Frozen ground
Languages : en
Pages : 46
Book Description
Special Report - Corps of Engineers, U.S. Army, Cold Regions Research and Engineering Laboratory
Author: Cold Regions Research and Engineering Laboratory (U.S.)
Publisher:
ISBN:
Category : Arctic regions
Languages : en
Pages : 478
Book Description
Publisher:
ISBN:
Category : Arctic regions
Languages : en
Pages : 478
Book Description
SIPRE Report
Depth-time-temperature Relationships of Ice Crystal Growth in Polar Glaciers
Author: Anthony Jack Gow
Publisher:
ISBN:
Category : Glaciers
Languages : en
Pages : 28
Book Description
The growth of ice crystals as a function of depth and time in polar firn and glacier ice has been investigated at a number of locations in Antarctica and Greenland. Thin sections of snow and ice were used to measure crystal size variations. Crystal growth rates are strongly temperature dependent with growth being very much retarded at the lower englacial temperatures. At Camp Century, Greenland, where the firn temperature is -24C (constant below 10 m depth) crystals grow approximately 23 times faster than at Plateau Station, Antarctica, where the in situ temperature is -57C. (Author).
Publisher:
ISBN:
Category : Glaciers
Languages : en
Pages : 28
Book Description
The growth of ice crystals as a function of depth and time in polar firn and glacier ice has been investigated at a number of locations in Antarctica and Greenland. Thin sections of snow and ice were used to measure crystal size variations. Crystal growth rates are strongly temperature dependent with growth being very much retarded at the lower englacial temperatures. At Camp Century, Greenland, where the firn temperature is -24C (constant below 10 m depth) crystals grow approximately 23 times faster than at Plateau Station, Antarctica, where the in situ temperature is -57C. (Author).
CRREL Technical Publications, 1950-1975
Author: Cold Regions Research and Engineering Laboratory (U.S.)
Publisher:
ISBN:
Category : Arctic regions
Languages : en
Pages : 284
Book Description
Publisher:
ISBN:
Category : Arctic regions
Languages : en
Pages : 284
Book Description
Physics of Snow and Ice ...
Monthly Catalogue, United States Public Documents
Author:
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 1250
Book Description
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 1250
Book Description
Abstracts of North American Geology
Author: Geological Survey (U.S.)
Publisher:
ISBN:
Category : Geology
Languages : en
Pages : 1048
Book Description
Publisher:
ISBN:
Category : Geology
Languages : en
Pages : 1048
Book Description