Creep failure of geomaterials and its numerical simulation

It is shown that creep failure of geomaterials can be simulated by a non-linear three-component elasto-viscoplastic model. The model is described in the case of a single stress variable and the isotach viscous property type, although the model can be applied to more general three-dimensional stress conditions and viscous property types other than isotach. Various trends of viscous behaviour, including stress relaxation and creep deformation with and without creep failure, are illustratively simulated to show that creep failure is one specific aspect of the whole viscous behaviour that can be simulated by a single model. Creep failures observed in drained triaxial compression tests on compacted moist cement-mixed gravelly soil and saturated soft clay are simulated.