03-28-2023, 09:47 PM
(12-18-2022, 01:11 AM)fontanj Wrote: Now the CRBE3 elements seem to be giving me trouble. I am getting singular columns in the stiffness matrix, and for of my RBE3 reference gridpoints, it says "EXTERNAL GRID PT. .... NOT CONNECTED".
The only way these grid points are intended to be connected to the model is through the RBE3 elements. They are used to distribute a point-force (applied at the RBE3 reference grid point) to other nodes. Does NASTRAN-95 not allow this?
Here are RBE3 definition in N95's UM.