Activation Energy for Creep of Spray Ice

Abstract

The activation energy must be known in order to relate creep rate to temperature according to the Arrhenius equation. In this note the activation energy for man-made spray ice is determined from primary and secondary (minimum rate) creep data taken from settlement readings and in situ pressuremeter tests at Mars spray ice island. Spray ice is used to construct drilling platforms in the Arctic Ocean, and the creep settlement is an important engineering consideration in design. The value of the activation energy determined from secondary (minimum rate) creep of spray ice was found to be 78 kJ/mol, for a temperature range of -2 to -22°C. This activation energy is within the range of activation energies reported for the creep of polycrystalline ice. The activation energy determined from primary creep data was highly variable and had a value of about 50 kJ/mol.