bold nut contact

[Jee-Bee]

Hi

i need a contact analysis between bolds and structure. Then is found a presentation about simular situation with or without preload.
I want check the same or related example in Freecad and calculix. Is this posseble?
see link for presentation: https://appliedcax.com/support-and-trai ... _Paper.pdf

[bernd]

very very interesting. I'm curious what _UR, Thomas and Harry can come up with if one of them will spend some time with this.

BTW: Kontakt is possible in CalculiX and in FreeCAD FEM too.

cheers bernd

[Jee-Bee]

I know contact is possible... but i need contact for bolds etc...
So (i expect that )i have to modify the contact calculation and i don't have a clue yet what i need to do...

[HarryvL]

Bolt pre-tensioning is alteady an option in CalculiX: https://m.youtube.com/watch?v=9SJpHRY5GXs.

I am looking into this and also into temperature loading as options for achieving pre-tensioning the cables for my bridge project: https://forum.freecadweb.org/viewtopic.php?f=18&t=27987

[thschrader]

I know contact is possible... but i need contact for bolds etc...
So (i expect that )i have to modify the contact calculation and i don't have a clue yet what i need to do...

Hi Jee-Bee,
here is an old model I have found (was a gift from UR_)

flange.FCStd

(498.04 KiB) Downloaded 34 times

https://forum.freecadweb.org/viewtopic.php?t=24041
youtube tutorial:
https://www.youtube.com/watch?v=Y9l1zYnMj4g

flange_bolt_contact.JPG (77.11 KiB) Viewed 1220 times

[Jee-Bee]

Thanks for both replies! It would be nice to have something simular in master sometime

[HarryvL]

http://web.mit.edu/calculix_v2.7/Calcul ... de233.html

"With the parameter SURFACE an element face surface can be defined on which the pre-tension acts. This is usually a cross section of the bolt. This option is used for volumetric elements. Alternatively, the bolt can be modeled with just one linear beam element (type B31). In that case the parameter ELEMENT is required pointing to the label of the beam element."

I will try the ELEMENT option for the bridge.