Author(s): Shirish V. Mulmule; Robert M. Adamson; John P. Dempsey
Linked Author(s): John Dempsey
Keywords: No Keywords
Abstract: Preliminary analysis of the fracture data obtained from the first two field trips during the large-scale in-situ arctic cyclic, creep-recovery and fracture experiments detailed in a companion paper by Adamson et al (1996) is presented. The ice sheet is assumed to be isotropic and the material properties are obtained from the crack opening displacement data co, ~ected. This data is then used to model the fracture of ice. A significant effect of the grain size to specimen size ratio on the apparent material properties of S1 freshwater ice is discovered. Fracture of sea ice revealed a nonlinear size effect on the nominal failure stress. Time dependent deformations strongly influence fracture. Fracture modeling is carried out using the fictitious crack model. An approximate time independent model which includes the experimental results for consistency is shown to predict the correct size effect on the failure stress. The size effect is also studied usillg the size effect law. Both approaches used to predict the size effect fail in the case of S1 freshwater ice hecause the dominant cause of the size effect is the lack of homogeneity. For S (! 3. ice comparable results are obtained using size effect laws as well as the fictitious crack model. The fracture energy for first year sea ice is obtained.
Year: 1996