Ice rubble pieces broken by bow impact and side hull of an icebreaking vessel usually pass along the ship's bottom hull and may hit the propeller/rudder or other stern structures causing serious damage to ship's hull. It is important to estimate the size of broken ice pieces during the icebreaking process. The dynamic interaction process of icebreaker with infinite ice sheet is simplified as a wedge type beam of finite length supported by elastic foundation. The wedge type ice beam is loaded with vertical impact forces due to the inclined bow stem of icebreaking vessels. The numerical model provides locations of maximum dynamic bending moment where extreme tensile stress arises and also possible fracture occurs. The model can predict a failure length of broken ice sheet given design parameters.
Natural resources development in Sakhalin area and the Sea of Okhotsk requires proper means of sea transportation from Russian Far East region to the energy consuming countries in East Asia, such as Korea, Japan and China. Sea routes in the Sea of Okhotsk are normally covered by sea ice of less than 1 m thickness from December to April and sea-going vessels should be equipped with sufficient icebreaking capability or at least ice-worthy hull structures.
Icebreaking operation in continuous level ice is a less difficult job comparing to works in other ice conditions like multi-year ice ridge field. Advancing ship's hull breaks the continuous ice sheet into small pieces and then those ice pieces moving along the side or bottom hull of the ship, often squeeze in between propeller and stern structure and make an impact on propeller/rudder or other stern structures causing serious damage to ship's hull. Therefore it is important to estimate the size of broken ice pieces during the icebreaking process.
