Me on CalculiX mailing list: Wed, 13 Jan 2016
Hi together,
I tried a simple beam calculation but it breaks with
*ERROR in gen3dnor: size of estimated
beam normal in 2-direction in node 1 element 11
is smaller than 1.e-10
It seams I am missing something fundamental ... Doe someone know what
the culprit is?
Attached the inp file.
Kind regards bernd
Answer from Martin Kraska
My answer again:The default mechanism for computing the normal directions of the beam fails if the beam tangent is in z direction, see doc for beam elements.
you can specify the first normal to be the y-direction, as your system is in the xz-plane:
*BEAM SECTION, ELSET=Mat0Beam0, MATERIAL=CalculiX, SECTION=RECT
20 , 20
0, 1, 0
It seams back in 2016 I was able to get around this by editing the input file for CalculiXThanks, Ahh I missed that. The other possibility would be use the
xy-plane. Both works well (If the beams are connected. They where not
in the file I provided.) But this works for 2D-construktions only.
How about 3D steel frame buildings. Taken into acount I would only use
rectangle sections. What could be done with a 3D rigid frame steel
building? There are beams in all 3 axis. As an example
http://www.b75.ch/download/rigid-frame- ... ilding.png
Bernd