High-speed imaging of mechanisms responsible for sawtooth cyclic loading during ice-crushing

Download
  1. (PDF, 456 KB)
AuthorSearch for:
TypeArticle
Conference19th International Symposium on Ice, 6-11 July 2008, Vancouver, BC
AbstractHigh-speed imaging (30,000 images/s) has been used to observe the behavior of monocrystalline freshwater ice during crushing at ?10°C. The ice contact zone consisted of an intact high-pressure central area surrounded by pulverized spall debris and partially refrozen melt. A sawtooth pattern was evident in the load record, similar to that observed in other ice crushing and indentation studies. The spalling behavior that is responsible for any particular load drop in the load record was found to be caused by the presence of small stable fractures in the high-pressure intact ice zone that were created during the preceding spall event and associated load drop. The small fractures are roughly centered in the intact ice region and this explains why the magnitude of the load drops is typically half the prior load value. The removal of ice from the intact ice zone by the viscous radial flow of a thin layer of melt has been described before (Gagnon, R.E. 1994. Melt Layer Thickness Measurements During Crushing Experiments on Freshwater Ice. Journal of Glaciology, 1994, Vol. 40, No. 134, 119-124). This process explains why the small fractures are roughly centered in the high-pressure contact zone. There the flow is stagnant and less ice has melted, relative to the non-central areas, and this leads to high non-uniform stresses in the ice that cause the fractures.
Publication date
AffiliationNRC Institute for Ocean Technology; National Research Council Canada
Peer reviewedYes
IdentifierIR-2007-49
NRC number6527
NPARC number8894919
Export citationExport as RIS
Report a correctionReport a correction
Record identifierb714e9e3-85eb-4025-9aa5-681cbcfd7e6c
Record created2009-04-22
Record modified2016-05-09
Bookmark and share
  • Share this page with Facebook (Opens in a new window)
  • Share this page with Twitter (Opens in a new window)
  • Share this page with Google+ (Opens in a new window)
  • Share this page with Delicious (Opens in a new window)