topic Concentrated force distribution on multiple points in Robot Structural Analysis Forum

Concentrated force distribution on multiple points

Anonymous — Wed, 14 Mar 2018 08:40:26 GMT

Hi!
What is the best way how to distribute a load on multiple beams from concentrated force with a condition that the force should distribute the force on one beam on multiple points?

I have tried using the rigid links by blocking master node to the slave nodes in Ux, Uy, Uz direction (see attached picture), but then i get disturbed bending moment diagram since the Ux, Uy between two points are not allowing rotations.

If i block the nodes in Uz direction i receive Type 1 instaliblity issues. I could add horizontal support for master node, but since i am planning to add some horizontal force, it is not going to work.

Cladding does not seem to work at all in this case.

I have managed to do the workaround by adding small colums (e.g. 5 cm tall ) with pinned bottoms in points where load shuld be distributed and by blocking the master/slave nodes in Ux,Uy,Uz and Rz directions (see attached second picture).

Although i am wondering is there easier way?

Re: Concentrated force distribution on multiple points

Rafal.Gaweda — Wed, 14 Mar 2018 11:40:20 GMT

Hi @Anonymous

Interesting.

Our results from our simplified model.

Re: Concentrated force distribution on multiple points

Anonymous — Wed, 14 Mar 2018 12:25:50 GMT

I just realised it is because i have beam offsets set to "upper flange" for all beams.

Is that a normal behavior? Even if all beams have the same cross section?

Re: Concentrated force distribution on multiple points

Rafal.Gaweda — Wed, 14 Mar 2018 13:55:40 GMT

I just realised it is because i have beam offsets set to "upper flange" for all beams.

Is that a normal behavior?

Yes.

Remove offsets.