Study on the Effect of Particle Shape on the Soil-Rough Interface Shearing Using 3D DEM

The soil-structure interface (SSI) is involved in many aspects of geotechnical engineering, with a range of efforts having been made to investigate the factors influencing its mechanical behavior. Its shear resistance and volumetric change are mainly governed by the soil properties. The particle shape emerges as an essential soil property affects various mechanical behaviors of the bulk soil, in terms of its compactness, the rotation of the particles, its shearing resistance, and so on. The particle shape effect must be properly considered as it pertains to the SSI issue. In this study, the interface shear tests are modeled using the three-dimensional (3D) discrete element method (DEM). Three types of clustered elements are used to represent the irregular particles, with the same relative density of the specimen being controlled before shearing. The effects of particle shape on the shear stress and volumetric deformation were analyzed, the specimen consisting of irregular elements showing a higher shearing resistance and larger dilation than the one consisting of spherical balls. The localization of shearing deformation was also investigated, with the finding that the thickness of the localized band is approximately four times that of the medium particle diameter.