Error optimize cross section??

Hi everyone,

I have a problem with the Optimize cross section component. I have copied and modified the CrossSectionValues.csv file so that it has only HSS square hollow sections and I imported through the Read cross section component in Karamba. Then I have selected the initial section through the Cross section selector. When I use the Optimize Cross Section component it appears the following runtime warning:

1. 388 cross sections need to be bigger than their biggest family member.

Could you help me to figure out what is the error?

You can see the gh definition in the image attached.

Many thanks in advance!

Attachments:

optimize cross section definition.PNG, 160 KB

Replies to This Discussion

Permalink Reply by Simona on September 19, 2016 at 5:43am

Dear Clemens,

Sorry to bother you again. How can I insert the rigid diaphragm constraint in karamba for the joints at the same z-level?

Many thanks in advance!

Permalink Reply by Karamba3D on September 20, 2016 at 12:35pm

Dear Simona,

you can define a nearly rigid joint by setting its stiffness to a high value (e.g. 1E5) for the translational stiffness in Z-direction via the input-plugs 'Ct' of the 'Joint-Agent'-component or 'Ct-end' or 'Ct-start' of the 'Beam-Joints'-component. Please see the manual for details.

You may have to test different values. If the spring stiffness is too large, a badly conditioned stiffness matrix results and the calculation gets inaccurate.

Best,

Clemens

Permalink Reply by Simona on September 21, 2016 at 3:44am

Dear Clemens,

I think that I've not explained well the problem. Looking at the deformed shape of the building, it doesn't have a global behaviour like a cantilever under the wind load and the top displacement is too high. I think that the problem is to insert the rigid diaphragm constraint, that is, I want the nodes of each z-level have the same displacement along x and y axis, and the same rotation around z axis. How could I do, please?

You can see attached the wrong deformed shape.

Many thanks in advance!

Best regards,

Simona

Attachments: