How to make a joint for beams if there are beams on both sides of an column?

Hello,

I am trying to make an structure in Grasshopper and I want to analyse the structure with Karamba. I know that Karamba needs to have nodes and joints on beams and columns to analyse the whole structure. I want to make this node seen on the picture.

There you can see that there are beams on both sides of the square column. How can i do it in my script? Cause i cant find anything to use it like this.

I have tried to use offset in Grasshopper for the beams so it can offset from the column, but now there is no connection between them, so Karamba cant read it/see it.

Attachments:

ExampleJoint.jpg, 322 KB
LinesTest2.0.gh, 116 KB

Replies to This Discussion

Permalink Reply by Lennert Loos on July 17, 2018 at 7:51am

Hi,

I guess this can be done by applying an eccentricity, but this will only work when only 1 beam is present indeed. When two beams are present, I would suggest to create some very (1000x) stiff (virtual) elements that fully transfer all loads from the beams to the columns and vice versa. In fact the blue U-sections on the image is exactly what these virtual elements are.

Hope this helps,

Lennert

Permalink Reply by Giorgio on July 17, 2018 at 8:16am

Hi Lennert,

Thanks for the reply, but is that even possible in Karamba? Cause if i understand it properly, what you mean is to make little small "lines/stiff elements" between the column and beams to give that line the properties of a U-profile with Karamba?

So in your example, the black lines are drawn and between them the yellow one who will be functioning as the transfer profile.

I hope there is a possibility in Karamba, otherwise my whole model would be kind of for nothing.

Edit: this is my new file, i have found something but its still not what im looking for. now i cant change the profile automatic.

Permalink Reply by Giorgio on July 17, 2018 at 8:22am

Here is the file

Attachments:

LinesTest2.0.gh, 141 KB

Permalink Reply by Lennert Loos on July 17, 2018 at 8:31am

The section doesn't really matter when the element has an 'infinite' or very high stiffness. It is just a way of transferring all internal loads between beams in an eccentric configuration. These elements are virtual and not aimed at representing the 'real' structure, also not for stress checks and so on...

Permalink Reply by Giorgio on July 17, 2018 at 11:56pm

I understand, but the thing is I want to represent the real structure kind off, since I want to export the whole geometry with the cross sections to Tekla with Karamba. Im getting there step by step, but now im stuck at this point. Here in my new file you can see what i want to try to get. I have made those beams "double", so in Grasshopper and with Karamba i can let those two beams move from the column in both directions, in my example to +y and -y direction. But now the beams are getting skipped one by one if i make more eccentricity components. Is this because of the list that is being merged and that GH is reading it not like the way i want it to?

EDIT: I got it, needed to graft my merge component :)

Attachments: