The subject of this study is estimation of extreme ice loads from drifting hummocks and hummocky fields, as well as those from the even ice fields of occasional recurrence which affect the marine engineering structures on shelf of the freezing seas. The authors have improved the previous deterministic model of dynamic contact interaction of drifting ice floes by simulation of frictional forces in contact. This model was realized as original computer animation model of ice floes impact, developed on the base of Delphi 7.0 software.
When designing ice-resistant platforms for the development of the largest Russian Arctic deposits, the reliable estimation of the design ice loads is necessary with the target level of safety during all the lifetime of the structure. The level of reliability of ice load estimations directly depends on quality and a degree of accuracy of mathematical models describing ice-structure interaction. Generally the ice cover of the freezing seas represents the composite spatially-non-uniform structure consisting of constituents various in the origin and properties, such as the rare and layered ice fields, first-year or perennial hummocks, hummock's rows, stamukha, and other ice formations drifting in water areas in condition of rarefaction with a various degree of unity (Bekker et al, 2001). In order to describe mathematically the formation of extreme ice loads on offshore engineering structures, first of all, it is necessary:
to select and analyze the design scenario with the ice cover including the analysis of the mode of a structure failure and target levels of structure reliability;
to develop the simplified mathematical models of interaction between the ice and the structure in every design scenario;
to determine design ice loads with the specified exceedance of probability for various ice conditions in every design scenario.
