From 1992 to 1994, a series of in-situ large-scale fracture and creep recovery/cyclic loading experiments were carried out to study the constitutive and fracture behavior of freshwater and sea ice. The tests were conducted during six field trips to the Arctic to study the physical and mechanical properties of lake and sea ice as well as the seasonal variation of these properties. The size of the test specimens ranged from 0.5 m x 0.5 m to 80m x 80 m covering a size range ratio of 1:160. The thickness of the first year sea ice in the latter instance was 1.8 meters.
The objectives were to determine the effect of specimen size on the tensile strength of ice, to establish an applicable fracture mechanics for sea ice and freshwater ice, and to explore the large-scale constitutive behavior of floating ice.
This presentation will focus on the progress made on these objectives. Specific topics to be addressed include the relevance and utility of size-effect laws to the field of quasi-brittle fracture, a viscoelastic fracture model for sea ice, and the issue of non-local effects (as in grain boundary sliding) and an adequate specimen size.
If time permits, the field of ice mechanics and ice dynamics will be discussed from the viewpoint of scale, and the capability to bridge scales from lab-scale to the Arctic basin scale will be assessed.
