Creep of snow and ice
Creep of snow and ice
复制标题
雪和冰的蠕动
DOI：
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发表时间：
1966
期刊：
影响因子：
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通讯作者：
J. H. Smith
中科院分区：
文献类型：
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作者：
M. Mellor;J. H. Smith
翻译后摘要：在单轴无侧限压缩恒载蠕变试验进行烧结雪和多晶冰的样品。雪的标称轴向应力范围为0.1至1.0 kgf/cm 2，冰的标称轴向应力范围为0.5至20 kgf/cm 2。研究的温度范围为-0.5 ℃至-34.5 ℃。假设蠕变遵循阿耳忒弥斯关系，在0.5 kgf/cm 2的标称轴向应力下，二次蠕变的表观活化能值从10.7 kcal/mole（密度为0.83 g/cm 3的冰）到17.8 kcal/mole（密度为0.44 g/cm 3的雪）不等。对于在-4 ℃和-10 ℃温度下承受0.5至20 kgf/cm 2应力的多晶冰，应变速率σ对应力σ的依赖性最好用σ = Csub 1 σ + Csub 2 σ的3.5次方关系式来描述，其中Csub 1和Csub 2是给定冰类型的常数。有人建议，蠕变的多晶冰取决于至少两个不同的机制，在应力范围内研究。如果每种机制都有其特征激活能，则蠕变实验中测得的表观激活能很可能随应力水平而变化。在雪受到一个给定的名义应力，这种影响应反映在变化的表观活化能与体积密度。（作者）
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/sq cm for snow, and 0.5 to 20 kgf/sq cm for ice. The range of temperatures investigated was from -0.5 to -34.5C. Assuming creep to follow the Arrhenius relation, values of apparent activation energy for secondary creep under a nominal axial stress of 0.5 kgf/sq cm varied from 10.7 kcal/mole for ice of density 0.83 g/cu cm to 17.8 kcal/mole for snow of density 0.44 g/cu cm. The dependence of strain rate epsilon on stress sigma for polycrystalline ice subjected to stresses in the range 0.5 to 20 kgf/sq cm at temperatures of -4 and -10C could best be described by a relation of the form epsilon = C sub 1 sigma + C sub 2 sigma to the 3.5 power where C sub 1 and C sub 2 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. (Author)