Journal of Cold Regions Engineering

Presented herein are ice-tank data concerning ice-rubble loads against a moored conical platform. Of prime interest is how rubble-ice loads are influenced by horizontal stiffness of the platform’s mooring system. An important, and heretofore undocumented, feature of rubble loading and clearing around the platform is the accumulation of ice rubble as a false bow, or prow, at the platform’s leading perimeter. The ice-tank data show that, under certain conditions of ice-rubble loading, the lowest stiffness of mooring tested resulted in prow instability and sloughing, which in turn lead to a cyclic pattern of loading, and to rubble congestion around the platform. An outcome of such rubble congestion was a marked increase in the overall rubble-ice load exerted against the platform.

The boundary condition for concentration of snow particles at the bed is necessary to calculate snowdrifts by a numerical analysis model. The flux type or the gradient type boundary conditions are reasonable. An idea of an entrainment coefficient of snow particle at the snow surface is useful. The values of the coefficient are considered to be a function of the density and viscosity of the working fluid and the properties of snow particles. In this paper, the values of the coefficient are estimated based on the $k–\epsilon$ turbulence model and the distribution of snow particle flux observed at the Mizuho Station, Antarctica in 2000, assuming the steady, fully developed flow over a flat snow surface. The snow entrainment coefficient is two or three orders smaller than the sand entrainment coefficient in a river. The reason is that the specific weight of snow particles in air is much larger than that of sand particles in water.