the analysis did not converge

[2014270234]

Dear STKO team,
I ran into the difficulties shown in the picture.Hope to get your answer.

[kesavapraba]

Hi, It is because you fixed Uz displacement under the sp constraint and then you apply displacement controlled analysis along the same Uz DOF at the control node. This will create the issue, hence ensure the DOF is free. I wonder why you did not perform gravity analysis before the pushover.

[2014270234]

Thank you very much. I did, but still no convergence.I'd appreciate it if you could fix the model for me.

[2014270234]

I did the gravity analysis before,but that was wrong,so I simplified it and just did the horizontal force analysis.

[STKO Team]

There were few errors:

• The torsional stiffness uniaxial material was too stiff (making the system ill conditioned)
• One fiber section was not used inside an aggregator (thus without torsional material) and without GJ -> singular in torsion
• The reference load is in the Y direction but you were controlling DOF 3 (Uz)!
• Don't use Lagrange Multipliers as constraint handler if you are not sure about what it does