Author(s): Knut V. Hoyland; Anders Mollegaard
Linked Author(s): Knut Hoyland
Keywords: No Keywords
Abstract: Two types of freeze-bonds were made in the UNIS cold laboratory. Pieces of ice were put together, submerged and tested. The dependency of their mechanical behaviour on the submersion time, initial ice temperature and sample size was investigated. The first set of experiments used big blocks and aimed at determining the spatial freeze-bond capacity and its variation within the block. The second set of experiments used cylindrical samples that were cut in the middle at 45°. In the big blocks experiment, the freeze bonds were stronger in the corners and on the sides than in the middle part of the block, and all samples failed along the freezebonds. This indicates that brine was pulled out from the sides and not pushed out by a freezing process. The freeze-bond capacity of the cylindrical samples firstly decreased with increasing submersion time and then stabilized. The initial temperature of the ice had a strong effect on the freeze bond capacity for short submersion times but less effect for long submersion times. The freeze bonds formed in 8 ppt water were stronger than those formed in 35 ppt water. The peak stress occurred when the freeze-bond temperature and salinity were both minimum, and supports the theory about freeze-bond brine volume determining the freeze-bond capacity in saline ice.