Abstract
As an ice sheet impinges on the surface of a cone, flexural failure takes place. That ice failure mode causes substantially lower forces than the case of compressive failure, which would take place if ice is to encounter a vertical structure. Previous work by the authors employed a numerical model of ice dynamics in order to predict ice failure patterns and forces on a conical structure. In an initial paper, simulations examined the role of the slope of the cone and the case of ice failure against inverted cones. That study indicated that the slope plays a role on ice loading. Later results, published at ATC 2014, then examined in more detail the roles of structure slope, friction on ice pile-ups and loading on a conical structure and compared the results with the analytical methodology presented in the ISO 19906 Arctic Offshore Structures standard. The present analysis continues to expand the work to examine the role of structure diameter on ice loading and pile-up height. Results are further compared to ISO 19906, with the objective of presenting concrete guidance for the current revision of that standard. Ice forces on upward-breaking cones as a function of structure slope, waterline diameter, ice thickness and ice-structure friction are presented. The results of the study are relevant for structures in ice, such as offshore drilling platforms, bridge piers and offshore wind turbine foundations.
