Crushing Characteristics of Dry, Wetted and Submerged Ice

摘要

In ice-ship ice or ice-structure collisions at sea with icebergs, thernmajority of contact occurs at the water line boundary where the icernsurface is in wet condition. Controlled ice crushing experiments havernbeen performed typically with dry-surface ice, such as Hobson’srnChoice tests. Ice crushing experiments with wetted ice have beenrnperformed, for example in the Polar Sea trials, but these experimentsrnlacked the controlled environment of laboratory crushing. There hasrnalso been a lack of comparative study between ice in dry condition,rnwetted and fully submerged condition. In this study, the effect of arnwetted ice surface is studied and compared to the effect of a dry icernsurface. These are then compared to the crushing characteristics of fullyrnsubmerged ice. These tests determine if any significant difference existrnin crushing characteristics between ice with a wetted surface and fullyrnsubmerged condition and compares both with dry-surface ice condition.rnAlso, effects of temperature and crushing speed were considered. Therntest results indicated that the wetted and fully submerged conditionrnresulted in a higher load level compared to a dry condition. Moreover,rntemperature and crushing speed had different effects on the dry andrnwetted conditions. The tests indicated that consideration must be madernto the effect of water in ice crushing tests for a clear understanding ofrnice behavior and for estimation of ice loads in operational environments.