Breakage and Morphology of Sands in Drained Shearing

Abstract

Particle breakage and particle shape are two prominent characteristics of carbonate sand. In this study, a series of drained shearing tests with different axial strains and confining pressures were performed to investigate particle-breakage development and particle-shape evolution under triaxial loading conditions. In addition, the correlations between particle-breakage evolution and particle-shape evolution and among the particle-shape parameters from both the specimen-scale morphology of all particles in a specimen and the grain-scale morphology of 3,200 grains in a specimen were studied. The test results showed that particle breakage develops with increasing axial strain and confining pressure. The relative breakage index has very strong correlations with the representative overall particle shape and the representative particle-shape parameters except the representative convexity. Moderate or high intercorrelations were observed for the particle-shape parameters of selected grains except convexity. Generally, convexity has the poorest relationship with the other three particle-shape parameters.