Observed Responses of a Saturated Sand under Constant Deviatoric Stress Path in Drained Triaxial tests over a Range of Applied Shear Stress

Abstract

The soil in embankment dams and slopes may accumulate irreversible deformation due to variation of water level. During that process, soil skeleton experiences constant deviatoric stress path, along with cyclic mean effective stress. In this work, triaxial drained tests were conducted under low rate of strain on saturated sand to investigate the strain response along such stress path, considering the influence of loading amplitude. Test results demonstrated that volumetric strain of saturated sand was diverse, when the consolidation stress conditions were different. When consolidation deviatoric stress was increased from 300 kPa to 900 kPa, the effect of amplitude of cyclic on the volumetric strain is strengthened, while the cumulative effect is weakened. The shear strain curves under different loading amplitudes were parallel to each other, no matter what the consolidation stress condition was. However, the cumulative shear strain showed great differences. Motivated by the effect of loading amplitude, the accumulation of shear strain was increased. While the consolidation deviatoric stress was held constant at a low stress level, the effect of loading amplitude on volumetric strain was greater than that on shear strain. However, with the enhancement of stress level, the effect on shear strain would be significantly enhanced.