large displacements

[statiker]

hi,

does anybody know a open software to analyze beams or columns with large displacements ?

 

[Ibanez08]

try calculix

 

[asixth]

Large displacement theory is something typically associated with tensioned structures where the structure will derive it's stiffness from it's geometry.

Not sure how to analyse beam-columns that way. There is a good text by Levy and Spillers on the subject but I not sure about software packages.

 

[GregLocock]

Assuming you mean displacements large enough to affect the load paths, then Calulix is not a great recommendation, it assumes linearity.

Any of the big general purpose FE codes will do this, but you will have to pay a lot for them. It will almost certainly be an add-on to get the large displacement codes.

Cheers

Greg Locock

SIGlease see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[GBor]

Correct me if I'm wrong, but I believe Calculix has a non-linear solver to handle Total Lagrangian displacement.

 

[GregLocock]

Wow, sorry about that, yes it does

http://www.dhondt.de/ov_calcu.htm

Cheers

Greg Locock

SIGlease see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[SamETABS]

you can usually do it by hand assuming 2 or maximum 3 beam-column elements, which can accomodate the geometry nonlinearity and material non-linearity.
I have used ADAPTIC which is house-made software in Imperial College London(google it!).
but you can access ZEUS as well:

http://mae.ce.uiuc.edu/software_and_tools/ZEUS-NL_Manual.pdf

But apart from software, you have to be able to set up the relevant matrix for geometry of the column to derive out its buckling load factor.
hope it helps...
Sam

 

[111213]

thank you all very much !

i found calculix, i will have a look...

i will also try adaptics, if possible

 

[111213]

samETABS:

do you know how i can get ADAPTICS ?

 

[LeHC]

I wrote a simple Matlab code (about 500 lines) that does the buckling analysis (and of course linear analysis) for 2D steel frames with tappered sections (I-beam and square tube). I can give for free. It has to be upgraded in order to do the post-buckling load-displacement analysis, if that is what you mean.

Attached is a screenshot of the output.