Inspection of three sophisticated constitutive models based on monotonic and cyclic tests on fine sand: Hypoplasticity vs. Sanisand vs. ISA.

The prediction quality of three of the most sophisticated constitutive models for sands has been examined based on a comparison of results from element test simulations and laboratory tests. Hypoplasticity with intergranular strain, the Sanisand elastoplastic model in the version of 2004 and the recently proposed ISA (intergranular strain anisotropy) model have been inspected. The laboratory tests performed on Karlsruhe fine sand used in the present study are freely available on the homepage of the first author. The model predictions have been inspected for drained and undrained monotonic triaxial tests with various densities and pressures and for monotonic tests with a few number of un- and reloading cycles. The main focus, however, lies on undrained cyclic triaxial tests with either stress or strain control and with different densities, initial stresses and stress/strain amplitudes. The strengths and weaknesses of the different constitutive models for various test conditions are worked out. • The parameters of three models have been calibrated for the same fine sand. • Different sets of parameters are necessary for monotonic and cyclic loading. • No liquefaction with hypoplasticity in case of stress or large strain cycles. • Buttery predicted by Sanisand for large strain cycles contrasts experiments. • All models work well for certain test types and show deficits for others. [ABSTRACT FROM AUTHOR]