Study on the particle breakage of coral sand in the ring shear experiment

Coral sand, a geotechnical material commonly encountered in geotechnical engineering practice, is susceptible to particle breakage under external loads. Particle breakage has always been a hot topic in geotechnical engineering. This study focuses on the detailed evolution of particle breakage in granular materials under large shear displacements by conducting ring shear tests on three graded dyed coral sands. In this study, image processing technology was utilized to quantitatively identify particles of different colors, and the breakage of particles in each particle size range within different graded sand samples was presented and analyzed. The results reveal significant differences between the actual breakage amount of particles and the relative breakage amount in most particle size ranges. Additionally, a linear relationship was observed between the absolute particle breakage rate in each particle size range and the logarithmic value of the normal stress. Finally, a new particle breakage index was proposed based on the detailed particle breakage analysis, which determined the breakage mode of coral sand particles under large shear displacement. These findings contribute valuable insights to understanding the particle breakage behavior of granular materials in engineering practice.