Tomography-based DEM simulation of Fujian River sand considering multiscale particle morphology

This study conducts tomography-based derivative discrete element method (DEM) simulations of Fujian River sand under triaxial shear. It contains the X-ray mu CT experiment for the particle morphology extraction, the digital twin-based model calibration for obtaining the model parameters, the spherical harmonic-based principal component analysis for the morphological gene mutation at different length scales, and the DEM simulations of virtual triaxial tests. 26 DEM samples were generated comprising three degrees of morphological gene mutation at different length scales. In this context, the particle morphology at each length scale can be successfully isolated to highlight its specific contribution to the allocation of external loadings within a given granular assemblage. It is found that particle morphology at different length scales plays a more crucial role in the various aspects of micro-macro mechanical behaviours of granular soils. The results of this study provide a novel viewpoint to systematically connect the micro-scale properties and macro-scale responses of granular soils under triaxial shear.