Internal joint
When meshing an object-based model into a finite-element model,
CSI Software automatically creates internal joints, indicated by a tilda (~) prefix, which supplement joints created at the ends and corners of structural objects. Joint coordinates and information may be displayed in tabular format through Analysis Results > Element Output > Objects and Elements > Table: Objects and Elements - Joints. Internal joints will have a blank entry under Joint Object.
Internal joints may also be displayed graphically when users select Define > Set Display Options > Display Options For Active Window > Labels, then deactivate the Joints > Invisible option, and then select Miscellaneous > Show Analysis Model (If Available).