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Thanks Prof. for the answer. If I change nothing else in my model other than the material for the twoNodeLink element, I get no errors. If I change the value of gap to 0.0 for the elasticPP gap, that also solves the error. Maybe using the gap material in series with another material will help.

Thanks

Hi,

I am using elasticPP gap material for two node link element to model a gap spring. I get the following error:
ProfileSPDLinDirectSolver::solve() - aii < 0 (i, aii): (74, 0)
Is elasticPP material only meant to be used for zero length elements or am I making some mistake?

Thanks
Abira Rather

Thanks Prof. for your answer. What I understand by your answer is that mid-point integration is by default implemented in openSEES for section integration. I read your blog post: https://portwooddigital.com/2022/02/06/two-fibers-explain-so-much/ and thought maybe we can change the type of integratio...

Hi, How can we select the type of integration scheme when using fiber sections (WFsection 2D, etc.)? Is the same integration scheme that is used for nonlinearBeamColumn elements along the length used for the cross-section integration as well? I hope that this question makes sense. Thanks Abira Rather

Anyone looking for similar errors, some of the reasons are mentioned below: 1. Negative Eigenvalues: One of the reasons that might be causing this error is not invoking wipe Analysis before starting an eigenvalue analysis. Not invoking wipeAnalysis after the application of gravity loads (i.e., stati...

Thanks for the reply @mhscott. Is there any documentation available that can help me understand these errors. I did find the following https://opensees.berkeley.edu/OpenSees/api/doxygen2/html/CorotCrdTransf2d_8h-source.html while searching for second error but I am not able to clearly understand wha...

Hi, I am running a dynamic analysis for a 10 storey 5 bay steel frame, both geometric and material non-linearity is considered. I am running a probabilistic analysis, using a sample size of 500. All the material properties and loads are modelled as random. Out of 500 simulations around 4/5 simulatio...

Ok, I got it. Thank you for answer.

Thanks Prof., I went through the post, it is about a bidirectional section. I want to know what model is used to determine stress resultant yield surface for a normal (unidirectional) fiber section in opensees. Can you please provide some information about that.

Thanks
Abira

Dear All,
What stress resultant plasticity model is used in OpenSEES?

Thanks
Abira

The output you are getting is not bending moment but it is the pseudotime. There must be something wrong with your code due to which it is unable to record the stress and strain and you are only getting pseudotime as an output. Thank you for your reply. Could you please help me to see how to modify...

The output you are getting is not bending moment but it is the pseudotime. There must be something wrong with your code due to which it is unable to record the stress and strain and you are only getting pseudotime as an output. Thank you for your reply. Could you please help me to see how to modify...

The output you are getting is not bending moment but it is the pseudotime. There must be something wrong with your code due to which it is unable to record the stress and strain and you are only getting pseudotime as an output.

Thanks

Dear All,
What quantities do the basicDeformation and plasticDeformation record for an element?

Thanks
Abira