"shell force" and "beam force"

Hello, everyone. I need to compare two structures to which a unit force is applied. One is a trellis and the other is a shell. I have to check, indeed make sure, that in each node the values of normal effort, bending moment and cutting are similar. First of all, how can N, M and V be obtained in the individual structures? The “shell force” and “beam force” commands give me a set of values but I can’t figure out where they are. If you could explain this to me and then how to make sure that the values are equal for the two structures.With Octopus?


The results of the Beam forces are listed according to the sequence of beams in your model, and the results of the Shell forces are listed according to the order of mesh faces.

Please see the manual for more information:

Yes this was clear to me! But how do I understand the results to which beam precisely correspond?
Let me explain, I’ll attach a photo and hope it’s clearer. I have inserted the panel to the output of the command “beam forces” in order to obtain My, returns me a series of results. Because there are three results for every point, and I don’t understand why every point has four coordinates. And especially to which beam corresponds every single result of the results obtained? How do I get the numbers legend on the 3d of gridshell? Please help me! I’ve already seen the manual and it’s not been useful.

Each separate list corresponds to a separate beam. For example List 0;0;0;0;239 corresponds to Beam Index 239 in your Model. If you are only using beam elements you can use the Disassemble Model to obtain all the curves in the same list order. The element tags in the ModelView also show the index of each element: https://manual.karamba3d.com/3-in-depth-component-reference/3.6-results/3.6.1-modelview#the-tags-submenu

Thanks so much

Hi @matttam
I want to know how to corelate the beam forces and shell forces with the elements when I have both beams & meshes in the model? In this case, does the path name in the list output signify anything?

Thanks a lot

the results of the beam forces and shell forces are organised so that each branch are ordered in the same order that you assemble the elements into the model. You can have multiple results for each element as you can see from the output of the results

Thanks for clarifying Matthew.
I get your 1st point on the results being listed in the same order in which the elements are assembled in 1st place.
But, can you please clarify your 2nd point on “multiple results for each element”? What does this mean?

Well depending on how many parameters you evaluate on each beam there could be multiple results - for example at the start, mid and endpoint of each beam.

Thanks a lot. That is helpful.