关键词: 北极科考, 海冰力学, 扩孔强度, 弯曲强度

Abstract: In-situ mechanical testing of Arctic sea ice is of great significance for ensuring the safety of ice navigation and supporting the design of polar ships. During the 15th Chinese National Arctic Research Expedition, systematic in-situ sea ice mechanical tests were carried out in the high-latitude region of the central Arctic Ocean (84°57′N-89°49′N). A total of 63 in-situ borehole strength tests, one full-thickness in-situ cantilever beam flexural strength test, and 43 small-scale three-point bending strength tests were completed. Among them, the borehole strength test and the in-situ cantilever beam test were both conducted by China for the first time in the polar region. Preliminary analysis shows that the borehole strength increases with latitude, rising from 3.9 MPa at 84°57′N to 14.2 MPa at 89°49′N. The flexural strength tests reveal a certain size effect: the full-thickness flexural strength obtained from the cantilever beam test is 226 kPa, while the arithmetic mean of the small-scale three-point bending strength is 384 kPa. This paper provides valuable field data for understanding the mechanical properties of late-summer Arctic sea ice and can support the design of China’s polar engineering equipment and the assessment of navigation safety of ships in ice-covered waters.

Key words: Arctic research expedition, sea ice mechanics, borehole strength, flexural strength