A Preliminary Analysis of the Crushing Specific Energy of Iceberg Ice under Rapid Compressive Loading

Indentation tests are used to study inelastic response of ice and other materials when loaded under a compressive stress state. Indentation testing provides force–time plots which are often converted to pressure–area curves, which can later be used in the design of ships and offshore structures. In an inverse application of indentation testing one can use the force-time response to extract material constants characterizing the extent of energy absorption, including dynamic hardness. The aim of the present study is to access the energy consumption index of iceberg ice as the ability to absorb the indentation energy. Data from indentation experiments conducted on natural iceberg ice at Pond Inlet in 1984 have been re-analyzed for three different sphericallyterminated indenter sizes. For any given test it was found that the crushing specific energy of the ice shows little, if any, dependency on the volume of the displaced ice and tends towards a constant value. Furthermore there is no apparent correlation of the crushing specific energy of the ice with indenter size, nor is there clear consistency in the values for tests conducted with the same indenter. Possible reasons for these observations are discussed