Experimental study on the effect of porosity on the uniaxial compressive strength of sea ice in Bohai Sea

For the abnormal ice condition in 2009-2010 winter, sea ice samples were collected in a tide ditch outside a port in the east coast of Liaodong Bay, and ice specimens were prepared. Experimental study was carried out with a temperature-control precision of 0.1℃, and 117 columnar-grained ice specimens were loaded along the direction parallel to ice surface under different test temperatures （-4, -7, -10, -13, -16℃） and strain rates ranging from 10^-6 to 10^-2 s^-1 within which the ductile region, duetile-brittle transition and brittle region are contained. The uniaxial compressive strengths, density and salinity of the ice specmens were measured. The results support the curved-surface relationship between the uniaxial compressive strength and porosity within a wide range of strain rate. The curved-surface relationship gives a quantitative description about the variations of the mechanical behavior transition point with ice porosity, and supplies a uniform mathematical representation of uniaxial compressive strength under different failure modes. Besides, it is deduced that abnormal ice condition in 2009-2010 winter will not result in a change of the uniaxial compressive strength of sea ice in Bohai Sea.