*MOHR COULOMB

Specify the Mohr-Coulomb plasticity model.

This option is used to define the yield surface and flow potential parameters for elastic-plastic materials that use the Mohr-Coulomb plasticity model. It must be used in conjunction with the MOHR COULOMB HARDENING option.

Related Topics
*MOHR COULOMB HARDENING
In Other Guides
Mohr-Coulomb plasticity

ProductsAbaqus/StandardAbaqus/ExplicitAbaqus/CAE

TypeModel data

LevelModel

Abaqus/CAEProperty module

Optional parameters

DEPENDENCIES

Set this parameter equal to the number of field variable dependencies included in the definition of the material parameters other than temperature. If this parameter is omitted, it is assumed that the material properties are constant or depend only on temperature. See Material data definition for more information.

DEVIATORIC ECCENTRICITY

Set this parameter equal to the flow potential eccentricity in the deviatoric plane, e. This feature allows the shape of flow potential in the deviatoric stress space to be controlled independently of the angle of friction. If this parameter is omitted, the deviatoric eccentricity is calculated by default as e=(3-sin⁡ϕ)/(3+sin⁡ϕ), where ϕ is the Mohr-Coulomb angle of friction defined on the data lines. The range of values e can have is 1/2<e≤1.

ECCENTRICITY

Set this parameter equal to the flow potential eccentricity in the meridional plane, ϵ. The meridional eccentricity is a small positive number that defines the rate at which the flow potential approaches its asymptote. The default is ϵ=0.1.

Data lines to define a Mohr-Coulomb plasticity model

First line

  1. Friction angle, ϕ, at high confining pressure in the p–Rm⁢c⁢q plane. Give the value in degrees. The friction angle can range from 0∘≤ϕ≤89.9∘.

  2. Dilation angle, ψ, at high confining pressure in the p–Rm⁢w⁢q plane. Give the value in degrees. The dilation angle can range from 0∘≤ψ≤89.9∘. Abaqus will set ψ to 0.1∘ when ϕ>0 and the dilation angle is not specified or is specified as zero.

  3. Temperature.

  4. First field variable.

  5. Second field variable.

  6. Etc., up to five field variables.

Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than five)

  1. Sixth field variable.

  2. Etc., up to eight field variables per line.

Repeat this set of data lines as often as necessary to define the dependence of the material parameters on temperature and other predefined field variables.