Session: 07-05 -01 Ice Model Tests

Submission Number: 177521

Real-Time Observations of Microstructural Evolution of Saline Ice Under Constant Pressure 

For many engineering applications, the compressive failure of sea ice during interactions with structures is a critical consideration. To this end, understanding the effect of compressive stresses on the evolution of the properties and behaviour of saline ice from microstructural to operational scales is critical. Previous studies have focused on post-test analysis of ice and lacked the ability to observe in-situ changes to the ice microstructure. Utilizing a novel apparatus designed to observe the effect of pressure on ice thin-sections under polarized light, observations of pressure melting and dynamic recrystallization of freshwater ice were observed in real-time. Foundational work by Galway et al. (2025), utilized a built-in borescope camera, polarizers and LED lighting to capture video data of the microstructural changes to the ice under selected temperature and pressure conditions. In those tests, freshwater ice samples (0.8mm thick, 60mm diameter) were grown in the apparatus and subjected to a constant 5 MPa compressive load at varying temperatures. The tests concluded that dynamic recrystallization was a key deformation mechanism, with grain nucleation dominating below -3°C, and grain boundary migration more frequently observed closer to 0°C. For warmed temperatures, pressure melting was observed resulting in rearrangement of the grain boundaries due to the applied pressure. The healing of cracks formed during initial contact was another important observation from those experiments. The current work aims to extend and build upon those results to study the effects of brine on the microstructural evolution of saline ice subjected to confining pressure. Using the aforementioned apparatus, the effects of pressure on saline ice will be investigated, to assess how internal stresses in the ice influence brine pocket formation and evolution processes. Small scale tests are planned covering a range of controlled temperatures and salinities, ranging from -20 to -2°C, and 5 to 35 ppt, respectively.  In this paper, preliminary results from these novel experiments will be presented together with a discussion of new insights into the understanding of ice failure under compression and its implications for engineering applications.

Presenting Author: Dylan Morawski Memorial University of Newfoundland

Presenting Author Biography: Dylan Morawski is a graduate student at Memorial University's Ocean Engineering department. His research focuses on ice growth and classification processes in laboratory settings.

Authors:

Dylan Morawski Memorial University of Newfoundland
Rocky Taylor Memorial University of Newfoundland
Jungyong Wang Canadian National Research Council