Effect of volume fraction and morphology of particles on the dynamic compressive strength of ice-silica particle mixtures

We investigate the compressive strength at high strain-rates of ice-silica particle mixtures with varying silica content. For this, we modify the split-Hopkinson pressure bar (SHPB) for low-temperature applications. Ice-silica particle mixtures with 4%, 8%, 12%, and 20% silica by volume are prepared by mixing crushed polycrystalline ice and silica particles. We have also probed the effect of particle shape by carrying out tests on ice-silica particle mixtures prepared using randomly-shaped, natural sand particles obtained from a local river basin, and spherical glass silica particles. The samples are tested at temperatures between 0 °C and −1 °C. We find that the dynamic strength of the ice-silica particle mixture initially remains unaffected at a lower volume percentage of silica and then shows an increase.

Ice-silica particle mixtures with glass beads, which exhibit greater overall regularity, exhibit lower strength enhancement compared to those prepared using the more irregular river sand particles for the same volume percentage. Based on our experimental results, we propose an empirical model that predicts the dynamic compressive strength of ice-silica particle mixtures, considering the varying volume fraction of silica particles and their morphology.