![using flac3d to model triaxial test for clay deformation using flac3d to model triaxial test for clay deformation](https://soilmodels.com/wp-content/uploads/2019/09/Pore-pressure-at-top-nodes-1.png)
All the three problems validate the model with the analytical, experimental and field data respectively.
![using flac3d to model triaxial test for clay deformation using flac3d to model triaxial test for clay deformation](http://docs.itascacg.com/3dec700/_images/modelnorsand-tri-undrained-pq.png)
After implementation and validation, the application of the particular constitutive model is extended to some practical geotechnical engineering problems like the stresses and displacements around an underground opening such as tunnels, surface settlement due to shallow tunneling, stress distribution below the footing, settlement analysis of footing on various foundation beds such as sand, clay and sand overlying clay bed, lateral displacement of the secant pile wall due to excavation and the force developed in the horizontal support etc. The principal aim of this work is to implement the endochronic constitutive equation in the FLAC3D model library like any other constitutive model and validate it with the triaxial test data. The dilation and densification behaviour can be predicted very well with the endochronic constitutive equations. It was proved that the equation proposed by Wu and Wang (1983) can be used to represent the triaxial behaviour of sand very well. the initial stage and combined to give the final state of stress. It is believed that a theory which violates the thermodynamic principle is not able to represent the material behaviour accurately. The classical theory of plasticity is developed based on the mechanical process. Experimentally it is very difficult to find out the yield surface in the case of three dimensional stress spaces.
![using flac3d to model triaxial test for clay deformation using flac3d to model triaxial test for clay deformation](http://docs.itascacg.com/flac3d700/_images/modelph-tri-undrained-devstress.png)
The expression for yield and potential surfaces are simply mathematical expressions formulated for computational efficiency. The definition of yield surface depends on the location of the yield point.īut in practical sense it is very difficult to find out the exact yield point for a material. The classical theory of plasticity is always associated with the concept of yield surface and potential surface to represent the plastic behaviour. All the existing constitutive models which represent the plastic behaviour of soil are developed from the fundamentals of classical theory of plasticity. Nowadays for most of the geotechnical engineering applications the elastoplastic models like Mohr Coulomb model are widely used. The major requirement for such analysis is a good constitutive model that represents the stress strain behaviour of the materials in an accurate way. The introductions of large digital computers in the field of engineering have rendered possible the solution of a wide variety of problems without the need to violate the equilibrium and compatibility.