equalDOF for local coordinates

[kyungtae79]

#..........o node 2 ..............^ Y
#........ /.........................|
#......./...........................|
#......o node 1................... -------> X (Global coordinates, Z is a normal direction of X-Y plane)

I have two nodes at the same location using the zerolength element.

In the local coordinates, the direction from node 1 to node 2 is defined as a longitudinal direction (which is local x).

Also, local z axis is a normal direction of x-y plane.

I want to constrain z-translation in local and theta-x in local.

To do it, I think that the only way is ...
Define the uniaxial material in the local degrees of freedom of 1, 2, 4, 5, 6. Then, Use equalDOF 1 2 3

Otherwise, is there any way NOT defining rotational material in 4, 5, 6 dofs?

[fmk]

you do not have to constrain or provide a material for every dof, people often leave out the rotational ones for example when doing a moment end release for a beam.

[kyungtae79]

Thank you, Frank

However, I need to constrain only rotation with respect to the local x axis NOT global X.

In this case, do I need to provide the material for this rotation?

Otherwise, how can I constrain the rotation only in the local axis?