Brittle failure of ice

This paper reviews the brittle failure of polycrystalline ice at temperatures (>0.8Tmp) and strain rates (∼10−7–10−1 s−1) of engineering interest. The discussion addresses ice as a material and emphasizes structure–property relationships. Tensile behavior is discussed in terms of the nucleation and propagation of cracks. Brittle compressive failure, a more complicated process, is addressed in terms of frictional crack sliding, wing cracking and a new mechanism termed comb cracking. The ductile-to-brittle transition under compression is modeled in terms of the competition between crack-tip creep and crack propagation. The paper closes with a discussion of leads in the Arctic sea ice cover and with evidence that failure mechanisms may be independent of scale. They may also operate in rock and other brittle materials.