A group of laboratory tests were conducted at Memorial University of Newfoundland with cylindrical ice specimens. The specimens were made with both laboratory ice and iceberg ice. In each test, the cylindrical specimen was triaxially confined at different pressure levels and an external constant deviatoric stress was exerted in the longitudinal direction. During the tests, some specimens showed a band of strain location in some cases leading to shear fracture. All those specimen showing strain localization or shear fracture made of laboratory ice were confined at relative low pressure levels (≤ 10 MPa) or high pressure levels (≥ 50 MPa). There was no strain localization or shear fracture observed at medium confinement levels. Strain localization or shear fracture observed in specimens made of iceberg ice was less pressure-dependent but initial flaws were observed in each specimen before the tests. Analysis shows that nonhomogeneity in the specimen is the likely cause of the localization. This has been confirmed by finite element simulations.
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