This project investigated plastic dissipation in granular media due to impact loads for potential stress wave tailoring and impact protection applications.
Consider a block of steel and a granular packing of steel. Due to geometry (spheres vs a bulk block), we expect the impact response to be very distinct. My PhD thesis quantified this difference.
The videos show impact on an elasto-plastic continuous solid half-space and on a granular packing made of the same material. The size of the plastic zone (indicated in red) is localized near the impactor in the first case, while it spreads over a large volume in the granular case.
Similarly, the energy dissipated is also significantly higher in the granular case. These differences arise due to stress concentration at the point contacts in granular media, thereby illustrating their potential for superior stress wave protection capability.
Journal Publications