| Summary: | Thesis (M.Eng.)--Memorial University of Newfoundland, 2003. Engineering and Applied Science Bibliography: leaves 119-127 Medium scale ice indentation tests were conducted at Hobson's Choice Island in 1989 and 1990. A damaged layer was found near the contact interface of the indentor and ice mass. The fluctuation of ice load is believed to be related to the layer. Triaxial small scale tests have been conducted at Memorial University of Newfoundland. The tests showed that microcracking is dominant at low confining pressure levels and recrystallization and pressure melting are dominant under high confining pressure levels. At the medium pressure levels, both the two mechanisms are inhibited and damage remains low. The tests also showed that increasing temperature has a softening effect on ice. The data of the tests is used to calibrate the damage parameter as a function of confining pressure and deviatoric stress. Strain localization and rupture observed from these tests are also studied. -- A constitutive model coupled with damage effects was established for finite element implication. Both the triaxial small-scale test and medium scale test are simulated by the finite element program, ABAQUS. Results of small-scale model show that inhomogeneity plays a significant role in triggering the strain localization and its consequent rupture. Results of medium-scale model are compared with the field data and they show a good agreement. The damage evolution process, stress state, energy flux and scale effect are also investigated.
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