The majority of Arctic class rules have been revised continuously based on collision experiences of small or medium size vessels operating in arctic area. IACS (International Association of Classification Societies) Polar Class Rules was also developed based on collision data for those small vessels with level ice and ultimate hull strength calculated from non-linear FE analysis. During the design of 107k DWT arctic tanker, which is much larger than the vessels utilized in rule development, several collision scenarios were provided through co-work between ABS, BMT Fleet and DSME to consider possible ice loads which IACS Polar Class does not cover. Three different collision scenarios were suggested for bow structure strength assessment. They are based on actual ice characteristics in Barents Sea. Besides level ice, ice floe and semi-ramming, which are not considered in IACS Polar Class, were also considered in collision scenarios. For each collision scenario, ice loads were directly calculated. Direct strength assessment through non-linear FE analysis was followed to verify bow structure design of 107k DWT arctic tanker.
Vast reserves of oil and gas are expected to be exploited in the Russian Arctic including the Barents Sea, the Pechora Sea and the Kara Sea. To transport crude oil, large crude oil tankers, which should be prepared for ice collision, are required. In structural point of view, ice loads as well as wave and current loads should be considered in hull design. However, ice loads are not familiar with ship designers since market demands were not so strong yet. With the increase of market requirement, lots of joint research works are under progress to consider the ice loads in design stage. So, we have researched the features of the Barents Sea and then we have developed ice load models based on these data.