I have a joint between a fitting (modelled by tetra10 elements) and a spar (modelled by cquad elements) in which each fastener is modelled by:
-RBE2 attaching 4 nodes of the fitting to central node 1 (DoF 123456)
-CBUSH between central node 1 and central node 2 (the same node duplicated). (PBUSH...
I am running a SOL 106 analysis and in the .f06 file I get:
USER FATAL MESSAGE 4658 (NPEND)
DIFFICULT GEOMETRY PREVENTS FURTHER COMPUTATIONS FOR ELEMENT WITH ID = 1970001
But this element is ok. This message appears after a 5 bisections without convergence in any step.