• Registered: 16-10-2010
  • Posts: 407

Re: output file 3d beam values

Ok, thanks, I made a fork on my github account of your repo. Is it the most convenient way? Some time ago you said something about the pull request, we can use that to exchange the code.

  • From: Gothenburg, Sweden
  • Registered: 08-09-2009
  • Posts: 1,419

Re: output file 3d beam values

Yes, that will work great.

  • Registered: 16-10-2010
  • Posts: 407

Re: output file 3d beam values

Mikael, how can I "import" your last commits in my fork? The pull request feature works only in the other way (e.g. I can ask you to import my changes but I cannot find how to have yours...).

  • From: Gothenburg, Sweden
  • Registered: 08-09-2009
  • Posts: 1,419

Re: output file 3d beam values

in git you can add several remotes. On a local machime you would just pull down changes from one remote and then push them to another. Im on vacation rigth now and i only have my phone, so i cant go into details.

Google for "git add remote" and "git pull remote"

  • Registered: 16-10-2010
  • Posts: 407

Re: output file 3d beam values

thanks!

  • Registered: 16-10-2010
  • Posts: 407

Re: output file 3d beam values

Dear Mikael,

Borek said that he took the beam formulation from here: Bittnar, Z., Sejnoha, J.:Numerical Methods in Structural Mechanics, Thomas Telford, Jan 1, 1996, simply replying the in-plane behaviour 2 times to obtain the 3d one.

In the meanwhile, with the fundamental help of a colleague of mine which is good with C++, the BEM export module is completed, you can see it in my github repo here.

I kindly ask you if you can have a look into it, I believe that (if the module is correct) there's still some errors in the beam3d code... In particular, have a look at the attached files, both with load sets:
1 - the test axial load only, named testN-Qk1, in which I obtain the wrong sign at the free end in the BEM output
2 - a test with distributed orth. load, in which Mzz have the opposite sign as the one excpected
I believe such errors derives from beam3d, there's no reason to change sign in BEM module...

Finally, in the attached zip there is also some screenshot of the book mentioned above with the derivatives of the sh. func.s we were looking for.

Thanks for your help,
Giovanni

Post's attachments

beam3d formulation and examples.zip 214.13 kb, 1 downloads since 2015-07-21 

You don't have the permssions to download the attachments of this post.
  • From: Gothenburg, Sweden
  • Registered: 08-09-2009
  • Posts: 1,419

Re: output file 3d beam values

Hi Giovanni

A few things:
1. Please fix the identation to use spaces instead of tabs in all the places you have modified the code. (Whitespace changes makes it hard to review code, as every line is marked as changed, it's best to change the editor to use spaces before committing changes in the future).

2. Please move the beamexport module over to the src/sm/export/  folder (and change the corresponding CMakeLists.txt files)

3.  I see you have made several changes to the B matrix in beam3d (if there are changes to the B matrix, then there should also be corresponding changes to the N matrix!)
Did these changes in the B matrix fix the sign errors you were seeing?

  • Registered: 16-10-2010
  • Posts: 407

Re: output file 3d beam values

Hi Mikael,
for 1. and 2. I'll push the changes asap.

3. yes, but I suppose that there was only a mistake in B and not in N, because the diaplcements are always correct if I remember well.
Anyway, no, reverting to the previous B matrix does not change anything with respect to the actual situation. I'll keep the commented lines in beam3d.c .

  • From: Gothenburg, Sweden
  • Registered: 08-09-2009
  • Posts: 1,419

Re: output file 3d beam values

Looking at your changes:

https://github.com/Micket/oofem/compare … web:master

I see multiple changes to the B matrix.

answer.at(2, 6) =   kappaz / ( l * c1z );
->
answer.at(2, 6) = (1 + kappaz) / (l * c1z);

and 

answer.at(2, 12) =   kappaz / ( l * c1z );
->
answer.at(2, 12) = -kappaz / (l * c1z);

and several more changes.

  • Registered: 16-10-2010
  • Posts: 407

Re: output file 3d beam values

Yes, but as I said, in the previously attached input decks the errors are the same. Anyway, I reverted to the previous B matrix.
I pushed the changes requested right now.

36 Reply by johnnyontheweb (edited by johnnyontheweb 24-08-2015 22:12:12)

  • Registered: 16-10-2010
  • Posts: 407

Re: output file 3d beam values

Hi Mikael,
I pushed another small correction on the export module, now I think it is complete. I kindly ask Borek and you if you can integrate the module inside the next OOFEM release.

Thanks,
Giovanni

EDIT: after a long testing, it seems all is working fine, except, as said, the sign of My from the solver (the export module is correct).

37 Reply by bp

  • bp
  • Administrator
  • Offline
  • From: Prague, Czech Rep.
  • Registered: 02-03-2007
  • Posts: 1,026

Re: output file 3d beam values

Hi,
the problem has been fixed now (hopefully) in the repository (http://oofem.org/gitweb/?p=oofem.git;a= … 8e8e155e80).
I have also added new Timoshenko beam tests to avoid any problem in the future.

Borek

bp's Website

  • Registered: 16-10-2010
  • Posts: 407

Re: output file 3d beam values

thanks a lot!