The problem of definition of platform concrete leg abrasion value at the variable level becomes more and more actual in connection with the shelf development in the arctic seas. However this problem is studied insufficiently that is confirmed by lack of certain guidelines in the norms of design. Investigations showed (Saeki H. et al, 1987), (Itoh Y. et al, 1995), (Itoh Y. et al, 1994) that the main factors influencing the concrete abrasion are as follows: the rate of pressure on ice contact with a structure, a way of interaction (abrasion) between a structure and an ice field in the contact zone, strength and temperature of ice, resistance of concrete and its ingredients to the abrasion. In practice, it is necessary to study local ice conditions carefully in order to calculate the depth of ice abrasion of marine concrete structures. The ice temperature is very important as it determines the ice mechanical properties substantially. When choosing a zone on the structures subject to abrading effect from ice formations in the certain area, it is necessary to take into account the most relevant factors, as follows: sea level fluctuation; variability of depth of the drifting ice formations; the mechanism of ice-formation collapse on contact with marine engineering structures. In the paper, the procedure of definition of the ice design temperature for calculation of the ice abrasion value. From the outcomes of the calculations it is possible to reveal the most unfavorable directions of ice cover impact and to determine the most abraded areas of a structure in the variable level zone, as well as to provide guidelines on an icebelt design with local reinforcements of the structure.
The ice abrasion causes loss of effective thickness and strength of structural components which should resist major ice loads.
