In addition, I raised the problem in another way. I added an area section to the bare structure and the result was the same: the only unfinished case was one of the two non-linear static.

So I consider that the problem could be plastic hinges, not the way I have formulated the non-linear case.

Pau Piquero

Your calculation does not converge, that is why you have a problem. Did you test the shear wall without the frame to see if it converges in non-linear analysis? You should take a look at the last converged step to see the deformed shape of your wall. Maybe there is a mesh problem.

Hi Damien, thanks for your quick response.

The shear wall represents a SIP panel.

Being a 2D analysis, I modeled the wall as an 18mm thick section area (9mm + 9mm), with a 10mm gap (Image 1, image 2, image 3).

Due to the simplicity of my shearwall, I didn´t test the wall without the frame. Now I just did it (infill_wof_model) and mark all the cases as "finished", with a total of 11 steps. However, the capacity curve remains linear and growing (infill_wof_curve.png).

What reasons could lead this model not to converge?

Thanks for the support.

I never used SAP2000 but can you change the numerical method to solve the equilibrium? The software might use Newton-Raphson and maybe it cannot converge in such a study. Another possibility is the apparition of too many hinges making the structure unstable.

I think the problem would be about iteration. Sometimes too many iteration process lead to divergence, so consider bigger time steps.