Simplified approach to characterize anisotropic strength of granular soils

Abstract

Experimental evidence shows that the strength of granular soils is significantly influenced by inherent cross anisotropy which cannot be properly described by isotropic failure criteria. This paper reviewed laboratory test results of various sands at different fabric directions. Based on the observations, this paper formulates the hypothesis that deposit plane creates a plane of weakness and the anisotropic strength of sands depends on orientations of deposit plane and failure plane. The strength decreases when orientations of deposit plane and failure plane are close to each other, and the strength increase when they diverge from each other. Then, an anisotropic failure criterion is developed based on this hypothesis and validated by available experimental data from literature. Remarkable agreements between predictions and measurements have been observed, which demonstrate validity, effectiveness, and robustness of new criterion in characterizing anisotropic strength of sands with variations of loading directions and intermediate principal stresses.