Author(s): Takatoshi Matsuzawa; Tadanori Takimoto; Haruhito Shimoda; Daisuke Wako
Linked Author(s):
Keywords: No Keywords
Abstract: Measuring ice load exerted on a ship hull is essential in order to build ice-going ships and to discuss ice class rules or guidelines, which exist for some locations, such as the Baltic Sea. In the southern part of the Sea of Okhotsk, the number of transits by ice-going tankers will be increasing in the near future due to the full activation of energy resource development. However, neither ice class rules nor guidelines have been set in this area, partly because of the lack of reliable field data. To address this problem, annual full-scale measurements of hull ice load of an icebreaker were executed from 2005 to 2009. Ice load was obtained by strain gauges installed on more than 10 vertical frames. The measurements were carried out over 1 week of travel in an icy sea on each February, and included observations of ice thickness, obtained by an electromagnetic measuring system, and ice concentration. The data showed that the maximum ice load increased along with the number of loading events. Our data trends can be explained by the relationships among peak ice load, ice thickness and ice concentration. We also analyzed the trends of ice load and ice conditions. We found a decrease in ice load over these 5 years, which could be due to the decrease in ice thickness.
Year: 2010