Effects of particle morphology on the shear response of granular soils by discrete element method and 3D printing technology

Abstract The development of quantitative correlation between particle morphology and shear responses of granular soils is an ongoing challenge. Herein, 3D printing technology, combined with the experiments and discrete element simulations were conducted to study the effects of different particle shapes on the particle migration, the development of shear zone, and the anisotropy of particle contact during shearing. Both numerical simulations and experimental tests confirmed that the increase of modified shape parameterS_hstrengthens the interlock between particles, which in turn limits the shear deformation in the direction of shearing. As the shear load increases further, the rotation of particles begins to develop from both sides of the shear box boundary, which gradually expands to the center, and finally forms a stable disturbance region in the center of the specimen; meanwhile, the positions of the maximum particle rotation appear at the center and boundary of the shear zone. Moreover, particle shape does not affect the distribution of fabric anisotropy before loading, however, the change of particle shape parameterS_hmakes the fabric anisotropy become prominent. In addition, particle shape is found to improve the shear resistance by changing the number and distribution of contacts between particles, rather than the contact force among particles.