An Elastic-plastic Ice Material Model And Iceberg Shape Sensitivity Analysis For Ship-iceberg Collision Scenario

With the increasing melting trend of sea ice in Arctic region, the north sailing route has come into reality. But icebergs exist in Arctic sea during the summer season; hence ship-iceberg collision is currently one of the hot topics in the ship collision research area. This paper addresses the research in two main contents: utilizing an isotropic elastic-plastic iceberg model to simulate the ice mechanical behavior and interaction of ship and iceberg in a ship-iceberg collision scenario; investigating the local shape sensitivity in ship-iceberg collision with using the proposed ice material model. The elastic-plastic material model is proposed firstly in this paper, numerical simulations of iceberg that strikes a tanker side and a ship bow are also presented. Impact force and energy dissipation results are discussed. Results from these simulations show that the proposed isotropic elastic-plastic iceberg material model can be employed to simulate the iceberg behavior correctly in ship-iceberg collision.Due to the complexity of the ice property, the effect of iceberg geometry shape on the collision process is also studied through predicting the ship-iceberg collision scenario with different iceberg geometry models. The simulation results including energy dissipation and impact force are investigated and compared. The blunt iceberg models act rigidly while the sharp ones crush easily during the simulation process if the elastic-plastic material model is adopted. A crushable foam model is also utilized for comparison. With respect to this model, the iceberg geometry has relatively small influence on the collision process. The spherical iceberg model shows the most rigidity for both iceberg material models and should be paid the most attention for design of ice-resist ships.The research results of this paper are useful for the structure design and safety of ships sailing in Arctic region.