FEM Reinforcement Results Comparing FreeCAD to Code Aster

[hhassey]

As I promised I ran a the FreeCAD Reinforcement RC Wall 2D example in Code Aster to compare the results. I hope this effort is useful for someone.

First I need to point out the following things:

• Of course both have the same geometry, same mesh, loading and boundary conditions.

• The Reinforced Material used in FreeCAD was made out of Concrete-EN-C35/45 for the matrix and Reinforcement-FIB-B500 for the steel.
  I was expecting the concrete to have a compressive strength of 30 MPA or 45MPA to my surprise it was set at 15.75 MPA (maybe someone should revise this number)

• Second, in Code Aster. There are far more parameters to use, there is a safety factor for the steel stress and one for the concrete stress, I set both to 1.

• Code aster calculates two layers of steel i.e Upper and lower steel. over the thickness of the shell, in this case both have the same stress and thus both results in code aster need to be added.

• Code aster reports it's reinforcement in m2 / m so in order to compare to the Reinforcement Ratio of FreeCAD I had to divide Code Aster result by 0.15m (the thickness of the shell)

Here are the Results:
FreeCAD:

FreeCAD Reinforcement.jpg (39.81 KiB) Viewed 1714 times

Code-Aster:

Aster Reinforcement.jpg (60.07 KiB) Viewed 1714 times

[bernd]

the colorbars seam sligthly different, but the result values seam equal ...

[bernd]

did you use the same mesh for both?

[hhassey]

the colorbars seam sligthly different, but the result values seam equal ...

That was the most similar I could find in CA.

And yes, I used the same mesh on both cases.

[bernd]

Since the same mesh was used, the nodal values could compared as well. Is it possible to print nodal values out of code aster? With an export from FreeCAD to Paraview this should be possible from FreeCAD side.

[hhassey]

Can you outline the process of exporting from FreeCAD to Paraview?

[david69]

https://wiki.freecadweb.org/Post-Proces ... h_Paraview

the wiki may help you.

[hhassey]

Here are the calculated displacements.

FreeCAD:

Displacement_Fc.png (54.16 KiB) Viewed 1580 times

Code-Aster:

Displacement_ca.png (49.62 KiB) Viewed 1580 times

[bernd]

Can you outline the process of exporting from FreeCAD to Paraview?

- In FEM workbench
- select the std FEM Result object
- Menue File --> export --> file typ --> FEM result VTK --> put in a name and press ok
- open the exported vtk file in Paraview

[bernd]

seams we (HarryvL) did a good job ... He was the one who initially developed the reinforcement force calculation.