Examination of particle shape on the shear behaviours of granules using 3D printed soil

Abstract

This study aims to advance the understanding of particle shape effects on the mechanical behaviours of granular materials by using 3D printed soil. A holistic particle geometry parameter (Sh), which integrated the 3D information of a particle (i.e. volume, surface area, and size) was developed to describe the particle shape and correlate with the granule’s shear behaviours. Test results revealed that higher Sh had positive correlations with the shear strength and dilation angle but exhibited negative correlations with packing densities. Under a constant relative density, particle shape showed coupled effects on the mechanical and volumetric behaviours of granular materials. The Regular Hexahedron (RH) granules exhibited the highest shear strength with the optimal shape parameter. In addition, an empirical correlation between Sh and maximum mobilised friction angle (ϕmax ) was established, which provided insights for discrete element method (DEM) simulations in considering the influences of particle shape.