XC, opensource structural engineering FEM code

[bernd]

I forgot to include an opensource in a former post

The other big problem is national standards. They are different in any country. There are dozens of opensource FEM software out there but none does implement national standards. The xc developer have started to implement swiss standard. Since I live i Switzerland too this is very interesting for me. On the other side as soon as a software has some standard implemented it is not that difficult to adapt this to other national standards.

All the proprietary do what harry wrote. They do implement national standards, but for every single module you have to pay and if you find a bug it is not sure they will gone fix it !!!

[ebrahim raeyat]

For GUI post processing paraview is state of the art. We have started to implement our own post processing in FEM but it is based on vtk, wiich is the library paraview is based on. IMHO the latter would be the best but takes resources to implement in FreeCAD. But one can switch to paraview all the time. Much more problems araise with pre processing. I am convinced structural analysis has to define the constraints (boundary conditions) an the geometry and not on the mesh. It is what all proprietary structural analysis software I know do and it is what FreeCAD FEM does. This is what makes FreeCAD FEM be somthing special in opensource FEM world, defining boundary condition on the mesh.

The other big problem is national standards. They are different in any country. There are dozens of (EDIT: opensource) FEM software out there but none does implement national standards. The xc developer have started to implement swiss standard. Since I live i Switzerland too this is very interesting for me. On the other side as soon as a software has some standard implemented it is not that difficult to adapt this to other national standards.

In the regard o GUI input for XC ... As I wrote I do not know yet what is best way to go. ATM I'm experimenting a lot with XC to get into their input format.

cheers bernd

1- we start? you and whom? is it opensource?
2- what is IMHO? I don't know any things about it.
3- for FEM software I want to use opensees. it is not micro FE program and is Macro FE. but it is exactly suitable for civil engineering.

let me say what i want to do:
A: preprocessing:

1. Geometry:point, line, area, solid all are in arch WB, but must be easier to implement
2. Define:material, section, load pattern, ...
3. Assingn: user select object any geometry and assign properties from predefined properties

when preprocessing is complete user can make OpenSees .tcl file and run that and then we read the outputs and go to next step:

B: post_processing:

1. Displacement: include Mode shapes and drifts
2. Forces: input and output forces for point, line and areas (countors)

C: Design:
it's for next level, but until that, there is no worry about provision codes.

thanks for your reply

[ebrahim raeyat]

The other big problem is national standards. They are different in any country. There are dozens of FEM software out there but none does implement national standards.

Dlubal RFEM allows code checks against international standards and national annexes. But is is bl&&dy expensive. And every time you want something special (non-linearity, buckling, etc) you need to buy another module. I have the basic modules and it is very good, but pre-processing (model definition) is less advanced than FreeCAD.

in my country (IRAN) civil engineers use CSI company softwares, for example we use Etabs for analysis of structures, unfortunately my country in not a member of WTO (Worrld Trade Organization), but i want to have an opensource program that would be under control!

[bernd]

I would not have expected most buildings in Iran will be analyzed with software based in California (USA)

Germany (where I'm from) and Switzerland (where I live) are member of WTO and there are dozens of Software around implementing Swiss and German national standard but I would like to have one open source solution anyway. I'm tired of endless discussions with support employers about bugs and important needed features and much less than i would expect happens ... A huge bill once a year they gone send anyway in any case ... Furthermore I like software with Python scripting API.

Bernd

[Jee-Bee]

Python 3 scripting API.

[kkremitzki]

I would not have expected most buildings in Iran will be analyzed with software based in California (USA)

I'm not too surprised, Iran is very seismically active, just like California. In fact the California professional engineering license exam has a special section just on earthquakes.

[ebrahim raeyat]

I'm not too surprised, Iran is very seismically active, just like California. In fact the California professional engineering license exam has a special section just on earthquakes.

yes, Iran is very seismically active. I studied in IIEES (International Institute of earthquake engineering and seismology) and now i am studiyng in Phd degree. my thesis was with opensees in SSI (soil structure interaction). you can find article here. I also work with linux and python for many years and I love opensource world.

[ebrahim raeyat]

although, we have our own codes in iran (and those are copy of ACI and AISC codes!), but we use ACI for concrete and AISC for steel sturctures, because they are in etabs and safe program.

[kkremitzki]

my thesis was with opensees in SSI (soil structure interaction). you can find article here. I also work with linux and python for many years and I love opensource world.

You might be interested in following this thread on relicensing OpenSees: https://forum.freecadweb.org/viewtopic.php?f=18&t=31922

Also, earlier you asked about 'IMHO', it just means 'in my humble opinion'.

[bernd]

if you have been working with linux I would suggest to give xc a try before you gone start to developing your own opensees based software.

Havw you been playing with FreeCAD FEM already, just to get into it?

Arch WB is volume driven, structural engineering analysis worldwide is structural axis and midface driven. In Arch WB we started to implement these axis and faces for walls and structures, but it still needs some love to work on most use cases. This is why Arch and FEM are not yet connected in FreeCAD.

Furthermore CalculuiX has no real beam elements and has some problems with them. Means it is not really good suited for structural analyses.

Thus Iam very interested in xc. Ahh and it already implements swiss national standars stuff.