Description:

Visualization of Drucker - Prager plasticity surface in principal stress space

What can be modified:

• yield stress in shear, τ₀,
• coefficient of internal friction, α
• 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)").
• Drucker-Pragerovy plasticity surface is a right circular cone with the top on hydrostatic axis.
• The section corresponding to plane stress results in ellipse.
• The deviatoric section results in circle.
• While modifying cohesion, the cone is translated along hydrostatic axis.
• While modifying internal friction angle, the top angle of the cone is changed.
• For zero coefficient of internal friction, the cone transfers to cylinder corresponding to Mises plasticity surface.