The Cam-Clay Material node adds the equations and interface for defining the material properties for the modified Cam-clay material. This material model requires the Geomechanics Module.

The Thermal Expansion (for materials) and Initial Stress and Strain subnodes can be added to the Cam-Clay Material.

The Pore fluid pressure pfluid is user-defined by default. The default value is 1 atm, but you can change it to another value or expression for the pore fluid pressure. If there are other physics interfaces (like Darcy’s law) in the model that make a pressure variable available, such variables will be available in the list.

To use a mixed formulation by adding the negative mean pressure as an extra dependent variable to solve for, select the Nearly incompressible material check box.

From the Specify list, define the elastic properties either in terms of Poisson’s ratio or Shear modulus.

The defaults for the Poisson’s ratio ν or the Shear modulus G, Density ρ, Cam-Clay M parameter M, Swelling index κ, Compression index λ, and Void ratio at reference pressure N are taken From material. For User defined enter other values or expressions.

Enter a value or expression for the Reference pressure for the parameter N prefN , the Initial void ratio e0,and the Initial consolidation pressure pc0.

If a study step is geometrically nonlinear, the default behavior is to use the Green-Lagrange strain in all domains. There are, however, some cases when the use of a small strain formulation for a certain domain is needed. In those cases, select the Force linear strains check box. When selected, a small strain formulation is always used, independently of the setting in the study step. The check box is not selected by default to conserve the properties of the model.

Physics tab with Solid Mechanics selected:
Domains>Material Models>Cam-Clay Material