ABAQUS: Loads on multiple points, single body

[lambosan16]

Hello.

I am kinda new in these topics of FEA and using Abaqus. I am trying to apply two concentrated loads to a single body by using reference points. I relate both reference points to the model by using Rigid Body constraints, and selecting the surface at which the point loads should be applied. Multiple messages of the following error appear: "NODE ### INSTANCE PART-1-1 HAS TWO RIGID BODY REFERENCE NODES 3 (ASSEMBLY) AND 1 (ASSEMBLY). NODES SPECIFIED IN A PIN NSET OR TIE NSET OR NODES WHICH ARE PART OF AN ELEMENT SPECIFIED IN AN ELSET MAY HAVE ONLY ONE RIGID BODY REFERENCE NODE". I tried creating a partition of the surface, thus relating the reference points to different surfaces, but it did not work either (same messages appeared, but with different nodes). What solution should I try?

 

[FEA way]

Each node can belong only to a single rigid body constraint. Partition itself won’t help because the nodes on the edge will still be common for both rigid bodies. You would have to exclude these nodes from one of the rigid bodies. You can create node sets manually to do that.

 

[lambosan16]

I solved the problem in a different way. I want to post what I did, for future reference and for those who encounter the same problem.

1. I meshed the geometry.
2. I relocated some of the nodes to my coordinates of interest.
3. I created node sets for each node in which I wanted to apply the point load.
4. Using the node sets, I applied the loads.

Did not figure out how to do it by only using reference points and not encountering the errors that I mentioned (mainly because I do not know how how to exclude nodes from one of the rigid bodies ). If someone manages to do it by only using reference point, and excluding the nodes (as noted by the comment above), please post how you did it for future reference.

As you can see from the image below, the forces are applied on nodes.