Creep failure of sands exhibiting various viscosity types and its simulation

The creep failure behaviour of three reconstituted sands exhibiting various viscous property types was evaluated by large-, medium- and small-scale drained triaxial, and medium-scale drained unconfined compression tests. The creep characteristics were evaluated by performing sustained loading during otherwise monotonic loading at a constant loading rate. Creep failure and Isotach viscous stress-strain behaviour were observed with well-graded Miho sand compacted heavily under the optimum water content condition. Creep failure of saturated and air-dried Toyoura sand exhibiting TESRA viscosity was observed at the nearly peak stress state. Degradation of the shear modulus of Toyoura sand during creep failure process was measured by the dynamic method. Creep failure did not occur with air-dried Albany silica sand exhibiting P&N viscosity. It was experimentally shown that the stability against creep failure was higher in order of P&N, TESRA and Isotach viscosities. The creep behaviour of various viscous property types was well simulated by the non-linear three-component model taking into account the effects of particle characteristics on the viscous property parameters.