Evaluation of the effect of anisotropic consolidation and principle stress rotation on underained behavior of silty sands

The dependence of undrained behavior of silty sand on initial state of stressand direction of principal stresses with respect to vertical () is assessed under generalizedloading paths using hollow cylinder apparatus. during applying shear load, value ofintermediate principal stress parameter (b) is held constant and  value is increased fromzero to the aimed value and held constant. specimens are consolidated, both, isotropicallyand anisotropically to evaluate the eect anisotropic consolidation on the behavior of thesesoils. the wet tamping method was selected to prepare specimen. shear loading was carriedout under strain-controlled condition to capture post-peak strain-softening response. theresults of this study reveal that the principal stress direction and initial anisotropy instress condition have considerable eects on the behavior of silty sands. by increasing ,susceptibility of silty sand to instability increases. in addition, increase in silt content ofsilty sand mixtures presents higher tendency to ow compared to pure sand. for specimenswith high silt content, it is observed that stress-strain response has a sudden reduction inshear strength after a peak. this study reveals that shear strength and steady state frictionangle of the silty sands are aected by  and the amount of nes present in the sand.