Connect to wall of a pipe

How would one connect plates to a pipe cross section as shown here:

so as to possibly produce deflections and stresses in the wall of the pipe due to a thermal, linear expansion in the pipe? or is this not possible with Karamba?

seems in order to connect members, their centers need to connect, and this negates the stresses in the wall of the pipe . . .:

Thanks in advance for any insight anyone may have!
Cheers!

Hi, your question relates more to analysis of the connection detail itself, so using standard beams in Karamba, this would not give you the result as you mentioned. You can split the horizontal members at the pipe radius so that you can locate the deformation and stresses in the elements at the connection.You can also do a detailed joint analysis using shell elements (modelling the real geometry using surfaces) or in another program such as IDEA Statica.

best,
Matthew

Thanks Matthew, some good ideas. I was hoping that I could do the entire vertical run of this which is like 10 bays at 15’ ea. but has 4 pipes, two heated, two not. Can I use Karamba to create the shell elements from the nurbs surface model? or would I need to mesh the whole thing & then . . . could Karamba handle that many shell elements? I was able to do an overall analysis of the beams, channels, pipes for the thermal load using SpaceGass & then do a single bay using ScanAndSolve but had to simulate the heat deflection using load vectors & it worked pretty well, but again I’m limited in ScanAndSolve by both the grid size and the Non-thermal load capability. I was hoping that maybe Karamba could do it . . . Any thoughts? Thanks again . . . Cheers!

Hi, you cannot simply convert the karamba beam geometry into shell geometry. You would need to mesh the entire model for the shell analysis. Just make sure your meshing is not too coarse nor too dense. However, as it is set up in grasshopper, this can be done parametrically so if you change your pipe radius, thickness, etc, it would be quite easy to adapt your setup. I am not sure what ScanAndSolve is but I could imagine a similar setup can be done parametrically.