Splitting-tests of laboratory-made granular ice with a propeller-like indenter

Abstract

Global warming will decline the sea ice in the upcoming decades. However, sea ice will prevail long enough in the sub-arctic and polar regions to remain a challenge for the shipping industry and arctic engineers. The decline in sea ice makes some economically interesting routes through ice-covered water more accessible. Still, at the same time, climatic changes can cause more dynamics of ice sheets and ice features. Therefore a bet-ter understanding of ice-propeller interaction is required with experimentally validated simulations. Propeller contact loads can be classified into milling loads and impact loads. The in-put ice property for existing numerical models of propeller ice interaction is usually the compressive strength at relatively low strain rates representing the impact scenario. Independent from the applied interaction velocity, a compressive test does not de-scribe the milling type interaction well, which is characterized by fracture and splitting of the ice. This paper describes the splitting-Test of laboratory-made granular ice with a propeller-like indenter. Splitting-Tests of granular ice specimens show no dependence on the L/D ratio. The force measurement during the splitting-Tests shows a dependency on the thickness of the inden-ter and, in addition, for the 6 mm wide indenter, a rate depen-dency. The force measurement of the splitting-Test with the 3 mm wide indenter shows no rate dependency. The higher specific strain energies in splitting-Tests of ice could lead to the lower measured forces.