Rotational dof's release. "-->Internal<---" steel connection

[xyont]

regarding rotational stiffness, it needed to use additional rigid arm similar case i has been discussed before. Fortunately, semi-rigid connection of both linear and nonlinear spring can be modeled.

Torsional Spring - SPRING2?

hi All, CalculiX only have translational springs, to modeling rotational spring some possibilities are shown in figure below. required eccentric two spring element (Kt) in the model and one additional nodes (red dot) connected by infinite stiff element or rigid body (gray line). best, [CCX_Equivalent_Rotational_Spring]