The equation of state of ice and composite frozen soil material

To compute shock wave propagation in frozen soil-water mixtures it is necessary to know a constitutive relation or an equation of state of the medium under consideration. Shock wave techniques provide a powerful tool for the investigation of equations of state at very high stress levels. The stress-volume behavior of frozen soil-water mixtures in the range from 60 to 500 kbar was investigated. Hugoniot data were obtained for Ottawa banding sand (pure quartz sand) and West Lebanon (New Hampshire) glacial till of varying degrees of saturation and for polycrystalline and monocrystalline ice (c-axis oriented in the direction of shock propagation). Release cross curve data were obtained for dry and saturated Ottawa banding sand and for polycrystalline ice. All materials were at an initial temperature of -10C. In all experiments plane one-dimensional shock waves were used. The Hugoniots and release curves for the soil materials show evidence of a quartz-stishovite phase transition at about 300 kbar. The Hugoniots of single and polycrystalline ice do not differ significantly over the stress range studied - 30 kbar to 300 kbar. (Author).