Viscous effects on deformation of kaolin clay in drained 1D compression with cyclic loading

Abstract

Viscous effects on the drained stress-strain behaviour of kaolin (D₅₀=0.001 3 mm; plasticity index(PI) is 41.6, liquid limit (LL) is 79.6%) were evaluated by performing a series one-dimensional(1D) compression tests on saturated specimens. Cyclic loading with a large stress amplitude was applied during otherwise monotonic loading at a constant strain rate. In the tests, one observation consistent with the previous research is that, significant loading rate effects on the stress-strain behaviour of saturated clay due to the material viscosity, not due to the delayed dissipation of excess pore water pressure, were observed during not only primary monotonic loading but also unloading and reloading. The results in cyclic loading show that creep deformation characteristics change significantly by preloading history, which is simulated by incorporating the viscous property into a non-linear three-component rheology model having isotach type viscosity with hysteretic inviscid stress-strain property.

Keywords

cyclic loading / rheology model / one-dimensional compression tests