Hello,

does someone knows how to create a rigid bar element in CCX? I need to set a point mass and connect it to the main FE structure via rigid element(s). The idea is to capture the inertia effects of a small body (point mass) in a modal analysis of a big structure. The added mass has no effects in terms of stiffness. I placed a point mass in a node at the center of gravity of the small body, but I dont know how to connect it to the main structure.

If I remember correctly, in NASTRAN the RBE3 would be a good solution. I am not sure if I can replicate it in CCX. I thought of using translation equations. One complication I thought is that we expect torsion of the main structure, so the translation of one node of the main structure wont replicate the rotation of the small rigid body.

I also thought I could set 3 beams with zero mass and almost infinite stiffness in an triangular arrangement.

Greetings,

Carlo