Hi to all,
I have a question regarding the restraint load in which the load in connecting node is different from the node where it connected.In this case the support is attached to an equipment, I assumed that the load should be the same because it is identical when it comes to its displacements. So, why does the loads are different?

Do you have a stiffness between the Node and the CNode? That would explain the difference.

for example,
...
FROM NODE 10 TO 20, AND NODE 20,CNODE 21
THEN THE NEXT ELEMNET IS:
FROM NODE 21 TO 30
...

IF YOUR ELEMENTS LIKE ABOVE EXAMPLE?

The stiffness between the node and the cnode is same with the CAESAR II default. In this case, the restraint type is +y with guide and is attached to the equipment. I am expecting same restraint load because Cnode is just an imaginary node that does not exist in the model and it is used only just to input displacement. In the case of anchor type restraint with cnode that is connected to equipment nozzle, the loads are the same but in case of +Y with Guide the loads are different.
What are the causes like in this case?

A CNode on a directional restraint only connects the two nodes in one direction. So if your Node is 100, and you restrain it to a CNode 1100 in the +Y direction then:

- if Node 100 wants to move down, it will remain connected to 1100 and both nodes will see the same load.

- if Node 100 wants to move up, off of 1100 it can. In this case node 1100 won't see any load from Node 100.

- if both nodes move up, Node 100 could have less load than 1100, if it is about to disengage from 1100.

You mean Cnode and Node would have different displacement? I thought the displacement between Cnode and node are Identical.
I my case only +Y has its value as user-defined displacement and the rest are zeroes. Based on the report, only FX forces are different, while DY has same displacement.

Another thing also that lead me into confusion is in the case of Node 3000 & Cnode 30001, it has same restraint load. I dont see any thing that differ from Node 2000 & Cnode 2001 in terms of displacements and restraint type input.

you can refer it in the attached report.

Did you define friction at that +Y?

Yes.!For guide I did not define friction.

Friction between a Node and CNode will result in different loads on each.

I think so, because when I did not define friction the loads are the same. Thank you very much Mr. Ay..!