Dynamic response of dry and water-saturated sand systems

The effect of grain size and moisture content on the dynamic macroscopic response of granular geological materials was explored by performing uniaxial planar impact experiments on high purity, Oklahoma #1, sand samples composed of either fine (75–150 μm) or coarse (425–500 μm) grain sizes in either dry or fully water-saturated conditions. Oklahoma #1 sand was chosen for its smooth, quasi-spherical grain shapes, narrow grain size distributions, and nearly pure SiO2 composition (99.8 wt. %). The water-saturated samples were completely saturated ensuring a two-phase mixture with roughly 65% sand and 35% water. Sand samples were dynamically loaded to pressures between 1 and 11 GPa. Three-dimensional meso-scale simulations using an Eulerian hydrocode, CTH, were created to model the response of each sand sample. Multi-phase equations of state were used for both silicon dioxide, which comprised individual sand grains, and water, which surrounded individual grains. Particle velocity profiles measured from the rea...