Effect of Fabric on Strain Localization Behaviour of Sands

The pertinence of fabric and dilatancy to the occurrence of strain localization in sand is investigated within the framework of a newly developed microstructure based constitutive model. It is argued that the fabric of sand governs its deformation mode and any subsequent localization into a shear band. Based on the premise that strain localization derives from material instability, the fabric dependent constitutive law is subjected to a bifurcation analysis in order to explore conditions under which shear banding is prevalent. The analysis shows that very loose sand can indeed display post peak behaviour and shear banding due to the consideration of fabric.