Fabric Evolution of Ellipsoidal Arrays with Different Particle Shapes

Fabric evolution of ellipsoidal arrays under drained triaxial compression loading was obtained by the discrete element method. The ellipsoidal arrays (specimens) consist of 520 identical ellipsoidal particles. The effect of particle shape on fabric evolution was studied by using four different aspect ratios (major/minor axis of the ellipsoidal particle) varying between 1.2 and 2. In the simulation, a large axial strain up to 80% was applied to the specimen. In addition to the typical macroscopic results, the fabric (microscopic information) of the specimen at certain stages was presented. The fabric includes the distribution of particle orientations and the distribution of branch vectors and normal vectors. Two distribution indicators quantified these distributions and one distribution indicator was identified to have direct variation with the principal stress ratio.