Field Studies on Response of a Floating Sea Ice Sheet to a Steadily Moving Load

概要

論文の詳細を見る
The results of a field experiment are presented and discussed. A skidoo was used as a moving load, and the test speed ranged from 0 to 14.2m/s. The thickness of the ice sheet was 0.17-0.18m, the ice temperature was -2.5 to -4.0℃ at the surface, and the water depth was 6.8m. The experimental results indicate the existence of a critical speed u_c, at which the ice deflection is amplified markedly , and its value is estimated to be 5.8m/s. At speeds above this value, two ice waves are generated, one ahead of and the other behind the load. At u_c the depression around the load is maximal in depth and minimal in width. The center of the depression begins to lag behind the load at fairly low speeds below u_c. Using the dispersion relation for flexural free waves in a floating ice sheet, a diagram that predicts the critical speed is presented. An understanding of the group velocity provides one explanation for the question of why two waves appear in front of and at the rear of the load. The two-dimensional deflection patterns obtains in the experiment are shown and compared with the existing theoretical results. At high speeds, the ice beneath the load is found to be not depressed but to be somewhat elevated. Reults also show that viscous damping has substantial effects on the ice deflection profile. The wavenumber curves, which give the two-dimensional wave patterns, are studies, and the results verify that the one-dimensional model is appropriate to discuss the wave characteristics in the present experiment. Finally, the ice response is classified into five stages.
北海道大学の論文
1988-03-30

著者

滝沢隆俊
北海道大学低温科学研究所

Field Studies on Response of a Floating Sea Ice Sheet to a Steadily Moving Load

スポンサーリンク

概要

著者

関連論文

スポンサーリンク