ttw0626 / multi_surface_plasticity Goto Github PK

In order to simulate the realistic shear modulus behavior, multi-surface plastic model is proposed by Mroz and further developed by Prevost. Multi-surface material model is able to match the G/Gmax curves by piecewise linear curves.

As the name implies, multi-surface model is composed of multiple yield surface in the deviatoric stress space. For each yield surface, the stress-strain curve is linear. The shear modulus becomes smaller after the stress states exceed each yield surface.

The multi-surface material models are implemented with a simple python-based GUI for testing.

Three yield surfaces were implemented for the multi-surface-material model.

• von-Mises
• Drucker-Prager
• rounded-Mohr-Coulomb

The mapping between multiple yield surfaces and the shear modulus reduction (G/Gmax):

The contact between multiple yield surfaces (ensuring non-overlaps):

The sample stress results and the modulus reduction results:

The cyclic behaviors of the stress-strain results:

sudo apt install python-tk python3-matplotlib

Tested on

• g++-7.4.0
• python 3.6.8

Prevost, Jean H. "A simple plasticity theory for frictional cohesionless soils." International Journal of Soil Dynamics and Earthquake Engineering 4, no. 1 (1985): 9-17.