Realisation and Modelling of Geotechnical Experiments

The realistic description of slope failure due to critical superimposed loads or heavy rainfall events remains a challenging research topic in soil mechanics. Here, the investigations concern granular materials, such as sand, which undergo a highly complex deformation behaviour that can be characterised via homogeneous triaxial experiments. Within this contribution, benchmark tests of base and slope failure situations will be presented, which are simulated by using the FE–tool PANDAS. The solid skeleton is described within the Theory of Porous Media (TPM) as a linear elasto–plastic material exhibiting an isotropic hardening–softening effect and a non–associated plastic flow behaviour. On the basis of triaxial experiments, the material parameters of the elastic as well as the plastic constitutive equations are determined using a gradient–based optimisation method, which is coupled with PANDAS. Finally, the simulations of the benchmark experiments and the localisation of the shear bands are carried out using either a biphasic model including a deformable solid skeleton and pore air or a triphasic model with an additional water phase (pore water) depending on the type of experiment. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)