ABSTRACT
True triaxial tests have been performed on tall prismatic specimens of dense Santa Monica Beach sand in a modified version of a cubical triaxial apparatus to study the effect of shear banding on failure in the full range of the intermediate principal stress. The experiments show that the strength increases as b increases from 0 to about 0.18, then remains almost constant until b reaches 0.85, and then decreases slightly at b = 1.0. Shear banding initiates in the hardening regime for b-values of 0.18 – 0.85. Thus, peak failure is caused by shear banding in this middle range of b-values, and a smooth, continuous three-dimensional failure surface is therefore not obtained in general for soils. Analysis based on theoretical conditions and experimental results agreed on the occurrence of shear banding and its consequent effect on the three-dimensional failure conditions for soil.
