A 3D finite-element model shown in Fig. 1 was developed to study pressures on the large diameter silo
wall used FEM software SAP2000. The element used to represent the stored material was 3D solid element, a
cubic element defined by eight nodes with three degrees of freedom and a nodal displacement at x, y, and z.
This structural element is compatible with surface-to-surface contact elements that admit different plasticity
models and laws of behavior of the bulk material. This study simulates silos filled with wheat, a granular
material that can be reasonably considered isotropic, particularly when it is randomly packed. Because wheat is
a granular material, a law of behavior of the stored material must be used that reproduces the behavior of wheat
grains with low cohesion. In this study, the bulk solid was simulated by Mohr-Coulomb model which was based
on a non-associated flow rule, a perfectly-plastic Mohr-Coulomb yield behavior and tension cut-off