The article discusses results of ice properties tests carried out in winter season 2018-2019 from 4 research sites located in the Laptev and Okhotsk seas. Field works were performed by the Russian Far Eastern Federal University as part of Rosneft Oil Company innovative program. This research has significantly expanded understanding of the ice strength seasonal variation and ice load on offshore structures in ice seas, and also made it possible to determine the optimal calendar periods for field tests. One of the main conclusions that can be drawn from the ice strength experiments is a linear dependence of the strength characteristics of flat ice on its temperature, while the coefficients in the corresponding regression equations depend on the region and type of ice. Approximate relationships between ice loads during the ice season are determined, new method for design parameters refinement is also proposed. The following conclusions can be drawn on the seasonal variability of ice strength and its effect on the value of design load the ice thickness at which it has maximum strength is 70% of the maximum ice thickness for the season; the ice thickness at which the maximum ice load is 80% of the maximum ice thickness for the season. The obtained results can be used for design and manufacturing of offshore facilities for exploration, production and transportation of hydrocarbons in the high seas of the Russian continental shelf, as well as for planning of marine along the Northern Sea Route.
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