Variations in physical and mechanical properties of model fine-grained ice during experiment

Evaluation of physical & mechanical properties of model ice is one of the most important aspects of experimental studies in ice basins designed to investigate ship propulsion and maneuverability in ice-covered waters as well as ice loads on engineering and hydraulic structures. These measurements in ice basins follow standard procedures across the world and comply with recommendations of the ITTC Committee. A certain specific feature of these types of experimental studies is that it is quite difficult to achieve the target thickness or strength values of model ice with a high accuracy. In this connection methods for correction of model test data have been developed and implemented. However, the time and frequency of measuring the ice properties remain an open question because the influence of experiment duration on variable physical & mechanical properties has been studied poorly. This problem is also caused by the fact that the test duration in modern ice basins capable of generating larger ice sheets varies depending on the number of test runs and particulars of studies. For investigation of this issue the Ice Basin of Krylov State Research Centre has conducted measurements in level ice modeled using FG ice technology and some conclusions have been drawn regarding the impact of air temperature on the main characteristics of FG ice type. The obtained results are aimed at reducing the uncertainty of model test results gathered in the ice basin.