Autodesk Video: Placing Analytical Links
An analytical link is an element connecting 2 separate analytical nodes. Creating analytical links simplifies and accelerates structural analysis of the model affecting the results to the acceptable extent. Analytical links may be used in certain situations such as connecting offset columns or beams, or modeling rigid floor diaphragms.
Analytical Links (An Offset Column and A Rigid Floor Diaphragm)
Analytical link properties except for marks are defined as properties. You can define rigidity of analytical links in the Type Properties dialog by setting translation and rotation conditions (as fixed or released).