Single Axis Constraint Reacting Moment

[alex.turner5PBCF]

Hi,

I have a Nonlinear Transient Analysis with three constraints, each only for one axis (Tx, Ty, Tz) and no rotational constraints. However,  they still output a moment in the SPC Summation, is there an explanation for this? I have not had this problem in more simple linear static models.

Thanks

Alex

[John_Holtz · Accepted solution]

Hi @alex.turner5PBCF 

The moment is not the sum of moment in the nodes. (If you are using a solid idealization, there are no moments in any nodes.) The moment on the SPC dialog is the sum of (reaction force * distance) + (moment in nodes), where the distance is between each of the nodes and the selected reference grid point. See this article for more details: Moment results on SPC Summation dialog not as expected in Nastran In-CAD or Inventor Nastran.