Ice rubble in the Arctic Ocean is a contiguous, random collection of ice pieces which accumulate in features known as first year pressure ridges and rubble fields. Knowledge of the mechanical properties of ice rubble is important in estimating the forces that such ice features may impose on offshore structures. Limited experiments have been carried out by researchers to measure shear strength properties of ice rubble formed under different conditions. The published data vary widely. Therefore, it has been difficult for engineers to decide on a shear strength value for predicting ice rubble loads for the design of arctic structures. An analysis of these reported data was carried out to compare these measurements and to provide some guidance in selecting these strength parameters for calculating ice rubble loads on offshore structures.
Ice rubble in the Arctic Ocean takes several forms, such as annual ice pressure ridges and ice rubble fields. Such accumulations, when formed in sufficient size, represent a threat to arctic offshore structures. Knowledge of the mechanical properties of ice rubble is needed for analysis of the interaction between these ice forms and arctic offshore structures and for the design of such structures. Ice rubble is a multiphase, highly complex material, properties of which are expected to be highly variable as a result of variable conditions under which it forms and ages. On a sufficiently large scale, however, ice rubble can be considered approximately homogeneous and isotropic, and its properties can be studied on a gross scale. Based on observations, it has been suggested that shear failure is the predominant failure pattern for unconsolidated or partially consolidated ice rubble. Limited experiments have been carried out by researchers to measure shear strength proper. ties of ice rubble formed under different conditions.
