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https://hdl.handle.net/11681/5879
Title: | Creep of snow and ice |
Authors: | Mellor, Malcolm Smith, James H. |
Keywords: | Ice Snow Ice creep Snow creep Stresses Strains Stress analysis Loads Viscosity Strengths Linear compression Ice formation Thermal effects Snow density Temperature factors |
Publisher: | Cold Regions Research and Engineering Laboratory (U.S.) Engineer Research and Development Center (U.S.) |
Series/Report no.: | Research report (Cold Regions Research and Engineering Laboratory (U.S.)) ; 220. |
Description: | Research Report Abstract: Constant load creep tests in uniaxial unconfined compression were performed on samples of sintered snow and bubbly polycrystalline ice. Nominal axial stresses were in the range 0.1 to 1.0 kgf/cm^2 for snow, and 0.5 to 20 kgf/cm^2 for ice. The range of temperatures investigated was from -0.5 to -34.5°C. Assuming creep to follow the Arrhenius relation, values of apparent activation energy for secondary creep under a nominal axial stress of 0.5 kgf/cm^2 varied from 10.7 kcal/mole for ice of density 0.83 g/cm^3 to 17.8 kcal/mole for snow of density 0.44 g/cm^3 . The dependence of strain rate ε on stress σ for polycrystalline ice subjected to stresses in the range 0.5 to 20 kgf/cm^2 at temperatures of -4 and -10°C could best be described by a relation of the form ε = 𝖢𝟣 σ + 𝖢𝟤 σ^3.5 where 𝖢𝟣 and 𝖢𝟤 are constants for a given ice type. It is suggested that the creep of polycrystalline ice depends on at least two distinct mechanisms in the stress range studied. If each mechanism has its own characteristic activation energy, the apparent activation energy measured in creep experiments may well vary with stress level. In snow subjected to a given nominal stress, such an effect should be reflected in variation of apparent activation energy with bulk density. |
Rights: | Approved for public release; distribution is unlimited. |
URI: | http://hdl.handle.net/11681/5879 |
Appears in Collections: | Research Report |
Files in This Item:
File | Description | Size | Format | |
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CRREL-Research-Report-220.pdf | 1.03 MB | Adobe PDF | View/Open |