In order to estimate the ice loads on marine structures in cold climate regions one should know how strong the ice is. Mechanical properties of ice are affected by a number of parameters and one of these parameters is ice density. The most common way to measure density is to evaluate the volume and the mass of the ice sample and calculate density directly as mass/volume. Despite its simplicity this technique is considered to be relatively inaccurate due to the difficulties in obtaining the true dimensions of the sample. An alternative way to do more precise density measurements is hydrostatic weighing in paraffin or in any liquid which has lower density than ice. This technique was applied for ice in a laboratory environment and proved to be very accurate. Present paper addresses a possibility of employing hydrostatic weighing technique in the field at ambient temperature. First, the paper presents density measurements performed in the Fram Strait during Oden Arctic Technology Research Cruise (OATRC2013) in August 2013. Ice density measured by a standard mass/volume method is compared with the results obtained by hydrostatic weighing technique. Moreover, a study on the effect of storing time on ice density results is reported. Second part of the test campaign is performed in the cold laboratory at Norwegian University of Science and Technology (NTNU). By applying factorial design of the experiment the effect of three factors: paraffin temperature, time of ice core storing and location of the sample in the core, and their interaction are studied. The results of the field and laboratory tests reveal no significant difficulties in performing density measurements by hydrostatic weighing in the field environment. Furthermore hydrostatic weighing method proves to be superior to the standard mass/volume technique.
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