Stress-Strain Behaviour of Cohesionless Soils Experiments, Theory and Numerical Computations
Cohesionless soils as for example sand show a very complex stress-strain behaviour depending on the stress state and the load history. To capture this material behaviour and, furthermore, to describe cohesionless soils under saturated and unsaturated (empty) conditions, an elasto-plastic model is used and presented in the framework of the Theory of Porous Media (TPM) defined by the elements mixture theory and concept of volume fractions. Within the constitutive equations of the elasto-plastic model, the elastic response is described by a materially non-linear elasticity law. Plastic deformations are considered in the context of a single-surface yield function with isotropic hardening properties. Non-associated flow is realized with an additional plastic potential function. Isotropic behaviour is assumed and the study is restricted to small strains. Parameter identification for the described model is shown for dense Berlin Sand on the basis of triaxial tests. The presented model is implemented into the finite element code PANDAS*, numerical examples will demonstrate the capability of the formulation.
KeywordsVolumetric Strain Triaxial Test Triaxial Compression Triaxial Compression Test Cohesionless Soil
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