STRENGTH ANALYSIS OF ICEBREAK RAMMING SEA ICE WITH EXTREME THICKNESS ALONG THE NORTHERN SEA ROUTE

In recent years, as a great increment in energy, the Arctic has become a focus for its abundant resources. However, the ice conditions are complex in this area, ships sailing along the Northern Sea Route (NSR) may collide with iceberg, ice sheet, ice ridges, etc. and resulting in structural deformation and damage of the hull. Therefore, the structural safety of the ice capable ships should be mainly considered. In order to estimate the structural safety of icebreakers encountering the sea ice with extreme thickness, numerical modeling calculation has been conducted in the simulation software LS-DYNA. Specifically, four representative sites are selected to predict the extreme thickness of sea ice, based on the statistics of yearly extreme sea ice thickness along the NSR. The ice-breaking conditions and bow stress patterns of icebreakers ramming the sea ice with extreme thickness at different speeds are simulated by numerical methods, and the extreme stresses of the bow ramming area are extracted. On the basis of the results above, the strength of icebreaker bow structure is checked with regulations to provide valid reference for icebreaker design.