Description:

Graphical representation of Mohr-Coulomb plasticity surface in principal stress space

What can be modified:

• cohesion, c
• internal friction angle, φ:
• the choice of displayed elements - it si possible to show or hide
• section corresponding to plastically admissible area for plane stress,
• axes corresponding to principal stresses,
• hydrostatic axis,
• plasticity surface itself.

Notice:

• View direction on the 3D picture can be modified with mouse (placing cursor on the picture, drag and drop).
• It is also possible to choose a predefined view:
• parallel to one principal stress axis (button "|| σ3"),
• perpendicular to hydrostatic axis (button "⟂ (σ1=σ2=σ3)"),
• parallel to hydrostatic axis (button "|| (σ1=σ2=σ3)").
• Mohr-Coulomb plasticity surface is a hxagonal pyramid with the top on hydrostatic axis.
• The section corresponding to plane stress results in hexagon with one axis of symmetry.
• The deviatoric section results in (non-regular) hexagon with three axes of symmetry.
• While modifying cohesion, the pyramid is translated along hydrostatic axis.
• While modifying internal friction angle, the top angle of the pyramid is changed.
• For zero internal friction angle, the pyramid transfers to prism corresponding to Tresca plasticity surface.