The effect of mode of loading on particle-scale damage

The effect of different modes of loading on particle characteristics of a silica sand is investigated. The particle characteristics were examined for samples taken to pre- and post- yield states in compression as well as after shearing to high strains. The change to particle characteristics such as surface roughness, shape and size due to loading were examined. The results show that although catastrophic particle breakage starts with the yielding of the material, changes to the particle surfaces at contacts, through minor damage to particle asperities by yielding or chipping, can impose some local changes even before reaching the yield stress. The study also confirmed the importance of the sample initial grading on defining the mode of particle interaction during compression.