Numerical simulation of sand deformation under monotonic loading and mesomechanical analysis

Based on the biaxial test by PFC2D, the behavior of sand with different densities under monotonic loading is simulated by discrete element method. The evolution law of macromechanism behaviors and mesofabric parameters is studied during sand soil progressive failure process. A statistic code is developed by fish language in PFC to study the evolution of microscopic fabric parameters including coordination number distribution, contact normal, normal contact force and shear contact force. The relationship between mesoparameters and macromechanical response can be achieved. The mechanism of induced anisotropy, compaction of loose sand and dilatancy of dense sand are discussed by using the mesofabric parameters. The results are valuable for the studying of mesomechanism of sand deformation and the construction of mesomodel for sand.