The response of natural snow to explosive shock waves

Field measurements of shock waves in snow with initial densities from 100 kg/m3 to 555 kg/m3 were made in situ in a natural snow cover. A high amplitude, short duration, uniaxial shock impulse (∼0.6 GPa for 10 μs) was imparted to the snow using sheet explosive, and the shock arrival time and stress histories were measured at depth in the snow. For dry snow (ρ0=250±30 kg/m3), the shock velocity can be described by a power law and decays rapidly with depth, from over 1000 m/s near the snow/explosive interface to 120±20 m/s at 0.20 m. The shock stress attenuation factor at a propagation depth of 0.20 m is about 4×10−3. Tests in which explosive gases were excluded from the snow had higher shock velocities and pressures than tests where the gases penetrated the snow.