Formulation of Cross-Anisotropic Failure Criterion for Granular Material

The failure anisotropy of geomaterial is inherently related to the microstructure such as grain arrangement, bedding, and crack pattern. This paper presents a formulation of an anisotropic failure criterion in three-dimensional (3D) stress space on the basis of the combination of the SMP criterion and a material microstructure tensor proposed in previous publications. The criterion is specialized for cross-anisotropic granular-material based on the loading direction and the direction of material bedding determined by two angles in 3D stress space. Consequently, it can describe the variation of strength resulting from the changing of the direction of material bedding and the changing of the stress state. Furthermore, the proposed criterion can capture the cross-anisotropic strength behavior of granular materials, which is concluded from the comparisons between its predicted and relevant experimental results. (c) 2012 American Society of Civil Engineers.