Cyclic test of metallic brace

[Hamza 13]

Good evening Dear colleagues,
This is a cyclic test of a metallic brace surrounded by a box of concrete. The brace resists axial loads (tension and compression), and its concrete role is to prevent this brace from buckling in the case of compression. There is a gap of 1 mm between the brace and the concrete to allow for free movement of the brace; the job runs successfully but without the desired curve.
What may cause this problem of unsmooth hysteresis loops? I tried with a finer mesh, minimizing the maximum step increments but no change, always the same curve with the sharp bends along the loops.
any suggestions from you will be welcomed.
Best regards,

 

[FEA way]

Which type of step is that ? What are the settings of output frequency for those variables ?

 

[Hamza 13]

it's static general step, and for the settings are set for the whole model and frequency for every n increments .

 

[FEA way]

Are the plots generated from field or history output ? In such situations, it's best to increase the number of increments (using automatic incrementation settings) and request history output every increment.