CGRG Bibliography of Canadian Geomorphology
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Author : Gold, L.W.
Date : 1997
Title : Statistical characteristics for the type and length of deformation-induced cracks in columnar-grain ice
Publication : Journal of Glaciology
Issue : 43(144):
Page(s) : 311-320
Abstract
Observations are reported on cracks formed during compressive, unidirectional, constant-strain-rate deformation of columnar-grain ice. The axis of hexagonal crystallographic symmetry of each grain tended to be in the plane perpendicular to the long direction of the grains and to have a random orientation in that plane. For stress applied perpendicular to the long direction of the grains, the deformation was practically two-dimensional. It was found that the relative proportion of grain-boundary cracks increased with increasing strain rate, decreasing temperature and, for strain rate greater than 5 x 10(-5) s(-1) with decreasing grain-size. Almost all the grain-boundary cracks had at least one edge at a triple point. For each test, the grain-boundary and transcrystalline crack lengths tended to have a log-normal distribution. The logarithmic mean crack length (LMCL) decreased with increasing strain rate, decreasing grain-size and decreasing temperature and tended to a constant value of 0.75 mm at -10 degrees C. For grain-size of 3 mm or greater, the LMCL had a maximum at a strain rate of 10(-5) to 10(-6) s(-1) at -10 degrees C. The LMCLs and the relative proportion of grain-boundary cracks tended to be normally distributed for given load conditions.
Bibliography of Canadian Geomorphology