Acoustic and mechanical properties of frozen sand

Compressional wave velocities at -10.0 and -3.2°C and the unconfined compressive strength show a dependency on the dry density of frozen freshwater sand specimens in the density range 1550 to 1780 kg/m3. Shear wave velocities are independent of dry density at both temperature levels. Acoustic wave velocities and unconfined compressive strength are independent of dry density when salt is added to the pore water prior to freezing. Increasing the salinity greatly reduces acoustic wave velocities and strength. These reductions are most pronounced when the salinity is between 0 and 5 ppt. Ultrasonic elastic constants were compared with dry density and salinity. Dry density and salinity tests should be included in engineering site investigations related to artificial ground freezing and frozen ground construction and acoustic measurements should be used to determine the elastic constants of frozen soils used in numerical modelling.