Response of a floating sea ice sheet to a steadily moving load

An extended analysis of previous experimental work (Takizawa, 1985) is made. Using the dispersion relation for flexural free waves in a floating ice sheet, a diagram that predicts the critical speed, at which the ice deflection is amplified markedly, is presented. An understanding of the group velocity provides one explanation for the question why two waves appear in front of and at the rear of the load. The two‐dimensional deflection patterns obtained in the experiment are compared with the existing theoretical results. At high speeds the ice beneath the load is found not to be depressed but somewhat elevated. It is shown that viscous damping has substantial effects on the ice deflection profile. The wave number curves, which give the two‐dimensional wave patterns, are also examined, and the results verify that a one‐dimensional model quite adequately describes the wave characteristics in Takizawa's experiment.