Effects of particle angularity on the bulk-characteristics of granular assemblies under plane strain condition

We investigate the influence of particle angularity on the stress–strain behaviour, rotation and micromechanics of granular assemblies under plane strain condition. Granular particles are modelled as regular polygons and numerical biaxial compression tests have been performed using the discrete element method. The packings consist of regular polygons with increasing corner number ranging from 5 to 64. The packings are analysed in the critical state in terms of their shear strength, bulk friction angle and porosity, as well as their cumulative rotation and contact characteristics with respect to varying particle angularity. We find that packings of more angular particles are looser but have higher shear strength, while packings of more rounded particles are denser, but are less resistant to shear. We further show that packings of angular particles are more resistant to reorganization by rotation, and that the mean rotation magnitude saturates at a constant value with increasing roundness. Lastly, we find that packings of more angular particles tend to have less contacts with higher normal and tangential forces when compared with packings of more rounded particles.