CONSTITUTIVE RELATION FOR A PARTICULATE MEDIUM WITH THE EFFECT OF PARTICLE ROTATION

The constitutive behavior of granular assemblies is investigated taking into account the effect of particle rotation. Continuum fields are assumed by tensorial polynomial expansion for the discrete variables, namely, particle displacements and rotations. The strain measures for the packing are obtained from the particle displacement and rotation. From the principle of virtual work, the stress measures for the packing are expressed in terms of the contact forces, the contact moments and the geometric measures for the packing structure. The derived stress-strain relationship is then evaluated by an example of a randomly packed assembly of circular disks loaded in two different conditions. Deformation of the packing calculated from the constitutive equations is compared with the results obtained from the discrete method of computer simulation to show the applicability of the method. © 1990.