N. Khalili, M. D. Liu
Dept. of Civil Engineering, The University of New South Wales, Sydney, NSW, 2052, Australia
Keywords: bounding surface, constitutive equations, critical state, dilatancy, plasticity, soils.
from simple elasto-plastic models, involving a single yield surface and a single plastic potential, to sophisticated constitutive models based on the sub-yielding of the material within the virgin yield surface, multiple yield surfaces, kinematic hardening and bounding surface plasticity among others (e.g., Proc. of 16th International Conference of Soil Mechanics and Goetechnical Engineering, 2005). The conventional elastoplastic models form the basis for a majority of the contemporary models proposed in the literature. The more advanced models are primarily used where the non-linearity and/or the cyclic response of the soil are concerned. Common to a majority of these constitutive models is the use of a stress direction independent plastic potential. This has rendered their numerical prediction for stress-strain behaviour of soils less than reliable particularly along complex non-proportional loading paths.