Discrete element modelling of relationship between ice breaking length and ice load on conical structure

Conical structures are widely used in marine engineering in ice-covered area because of their icebreaking capability. The ice loads acting on the conical structures are closely related to the failure modes of sea ice. The discrete element method (DEM) is adopted to simulate the ice failure modes and ice loads during the interaction between sea ice and conical structure. In this study, the accuracy of DEM simulations is validated by comparing the simulated ice loads with the measured ice loads from the model tests in Hamburg Ship Model Basin (HSVA). A bending failure occurs when the sea ice interacts on the conical structure, and the sea ice breaks into many fragments with different breaking lengths. The influence of ice thickness, ice velocity, cone diameter at waterline and cone angle are considered to analyze the characteristics of ice breaking length. The simulation results show that the ice breaking length increases with the increase of ice thickness. The increase of ice velocity and cone diameter can lead to the change of sea ice failure mode, which can reduce the breaking length of sea ice and increase the ice load. The decrease of ice breaking length indicates that the failure mode of sea ice changes from the bending failure to the crushing failure. A static ice force formula considering the effect of ice breaking length can be proposed to predict the ice load of the structure and verify the reliability of the structure.