The objective of this research is to study the mechanics of granular material from micro-structural point view to obtain the stress-strain relationship. The focus of this research is to formulate the stress-strain relationship for large strain problems with a continuum representation which will be studied with particular attention to the fundamental understanding of the behavior of granular systems, such as energy dissipation, stress- dilatancy characterists, etc.. The objective will be achieved by redefining the continuum variables, stress and strain, in terms of contact forces and micro geometrical measures. The stress-strain relationship will be developed by considering the sliding, and rotation of the particles. The theory will be then extended for pickings made of multi-sized and non-spherical shape particles. Experimental studies on assemblies of rods and computer simulation will be conducted to aid the development the theory. the results from the experimental studies and computer simulation along with the available date from studies on natural granular systems, such as sands, will be used to validate the developed theory.
