Showing results for 
Search instead for 
Did you mean: 

Determining Torsional Stiffness of a C Bracket

Valued Contributor
Valued Contributor



I have a C bracket (picture). I am trying to determine the torsional stiffness of the structure.


I have applied unit loads at the two lugs at each free end (torque) and held the supported section (middle) of the bracket.


The issue that arised is when I compare the deflections in the Z direction (local axis) and determine the twist angle is not the same as when I view the nodal R1output (local axis). 




C Bracket.PNG


Any ideas on why this is so? I would expect them to be the same.






Re: Determining Torsional Stiffness of a C Bracket


I do not know exactly what you are doing. Some plots may be helpful


But if you want to measure the torsional stiffness I would determine the rotation of the node at the middle point between two points where the load is applied .How?Maybe using RBE3 and connecting a central node with the locations for the loads can be helpful. You apply the moment there.Then you measure the rotation of this central node . Stiffness=moment/rotation