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Hi, please contact me using this forum! I don't have lastest version of OpenSees,but in my version (1.7.3) I used the command: 'remove loadPattern $number of pattern$' So you can do an eigenvalue problem at every single step of analysis. Another way is to use 'save' and 'restore' commands, but in my...

Hi Stefania. Well: 1)no, they are not; 2)you have to do a simple script to normalize the eigenvectors (see the sripts posted by silvia on eigen-analysis); 3)there's an adaptive pushover in the air,isn't there? So, yes, you can get eigenvectors on every step of analysis, just do it proceding step by ...

Hi! I have a problem me too with displacement-adaptive pushover. At each analysis step t I calculate the target displacement of every floor from a relation : U(t)=U(t-1)+λ*D(t), where U(t-1) is the displacement of the previous step, D(t) is a displacement vector that I calculate from eigenvalue ana...

Hi all! I've developed a script to perform a displacement-based pushover. It is a bit complicated, but it seems to work. The problem is that the resulting interstory drifts I've obtained with it, doesn't accord very well with those of the non linear time history analysis. The procedure should work b...

Hi all, what's the problem with an eigenvalue analysis outputting error: 'domain error: argument not in valid range'? I'm on an adaptive PO where the forces are updated during the analysis. The algorithm is: 1. apply a force distribution to the structure 2. reach a first target displacement (with di...

Thanks!

Hi all! I’ve some doubts about reset and loadConst commands. I’m trying to perform subsequent dynamic analysis on the same model for IDA-analysis construct. The algorithm is the follow: 1) perform static analysis for vertical loads 2) set loadConst –time 0.0 3) perform dynamic analysis for the actua...

Ok,
all seem right introducing a little hardening ratio (0.005) in Steel01 material.
This probably avoid negative or zero stifness values during analysis.
I think.
Thank you for the assistance.
Ciao Silvia, sapevo che eri italiana!
Best regards.

Hi! I’ve got some convergence problems with a dynamic time history analysis. The model I’m using is capable to reach deformation at top floor of 1%-2% of the total height with a static pushover analysis, but with dynamic analysis it doesn’t reach even 0.5%. However I’ve noticed that the problem duri...

Hi! I am looking for the relation to compute ultimate strain for the concrete04 model. The relation I have is: ecu = 0.004 + 0.9*%a*(fy/300) (mod.Scott,Park & Priesteley) (fy in N/mm2) (%a is the shear reinforcing bars percentage) but its values seem to be so low... Any suggest? (sorry for mista...

Hi all! I have two issues.. First: there are commands like ‘nodeDisp’ or ‘nodeVel’ to check other parameters of the structure like stiffness, local deformations, etc.? If not, how can I check them? For ex. if I want to stop the analysis when a target deformation is reached by concrete or steel, how ...

Hi, I'm a new user, so sorry for my not-so-professional-questions! And sorry for my not-so-good English, I’m Italian! I've noticed some little differences in the behaviour of the elements depending by the number of integration points choosen. Increasing number of int.points the structure should reac...