Beam subjected to moment only

[isok89]

I have subjected a thin-walled beam to a moment load only by
using references point on both ends (supports).

- Shell elements
- Implicit dynamic solver with quasi-static application
- moment applied at supports

The supports (total cross section EDGES due to shell elements at the supports) are constrained by 'pin nodes'towards the reference points. On these reference points I have applied the support
boundary conditions and the moment

However in results my applied moment does not reduce after failure.I clearly see in the animation (scale factor =1) that the beam completely fails but my applied moment in the results stays the same until the simulation aborts due to extreme deflection.

The beams I use should immediatly fail after reaching ultimate load.

Before I used a three-point bending model and everything worked accordingly (peak ultimate load). Right now I switched to moment loads at the supports and am having this problem.

Any solutions?

 

[isok89]

To summarise the above:

I want to create a moment - displacement curve instead of load - displacement curve.
What I basically want to know is the bending moment in my section in time history.

If someone could please help me, I already tried using Section moments in field variables
but I'm not getting a definitive answer. Have been struggeling with this for a few days.