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Dear all, I have a question about the displacement recorders in opensees. In version 2.1.0 there is a command which returns the displacement or rotation at specified node: nodeDisp $nodeTag $dof also we have a node recorder command: recorder Node <-file $fileName> <-xml $fileName> <-time> <-node ($n...

Hi I am doing a pushover analysis on 2D frames. I wanted to know if it is possible to make every story rigid or not? I've used "elasticBeamColumn" command with very high value for moment of inertia to make beam elements rigid. But for column elements, I've used "nonlinearBeamColumn&qu...

Thanks! Eigen analysis works properly but the problem arises after that. I'm using "sp" load command to impose predefined displacement at some nodes. In 3D models, we choose master node as a representative in each story, but in 2D model "rigidDiaphragm" command is not usable any ...

Hi I want to do a pushover analysis on a 2D steel frame. I have done some pushover analyses on 3D models before. In 3D models, we could use reigidDiaphragm command to make every floor rigid but in 2D models, this command is not usable any more. So two problems is released here : 1.While performing e...

Hi What is the difference between these two recorders : recorder Node -file def_mode_1.out -node 9902 9903 -dof 1 2 3 eigen 1 & recorder Node -file def_mode_1.out -node 9902 9903 -dof 1 2 3 "eigen 1" I want to calculate modal shapes but these two recorders give different results so I d...

Hi
The topic here is about elastic response spectra. I wanted to know about inelastic response spectra. Can we generate inelastic response spectra with this algorithm?
Than you very much!

Hi I am modeling 3D structures in OpenSees. I have modeled a six story (3D) building and I want to perform some pushover analyses. But the problem is that it takes a long time to finish the analysis! Even for gravity analysis, it takes about 4 or 5 minutes to finish the analysis! I just wanted to kn...

Hi I'm using OpenSees for 3D modeling. I wanted to know about the period difference between same models in OpenSees and other programs. For example for a 2 story (3D model) first mode period is 0.7 in OpenSees but 0.65 in SAP or ETABS. I just wanted to know if this difference is acceptable or not?! ...

Hi all,
I still have the same problem and I couldn't solve it. I'll really appreciate if anyone could help me to solve this problem. I've posted the modeling part of my script. Can anybody find any problem in this script?

Thank you very much

Hi I have a question about "plot recorder" command : recorder plot $fileName $windowTitle $xLoc $yLoc $xPixels $yPixels -columns $xCol0 $yCol0 <-columns $xCol1 $yCol1><-columns $xCol2 $yCol2> ... I can't understand what we should put instead of $xCol0 & $yCol0 parameters! I have read t...

Hi I am doing some pushover analyses with opensees and I have a question about usage of damping in static analysis. In opensees examples (I mean in opensees example manual), for static analyses, damping is not used but in dynamic analyses it is used. I wanted to know the reason of that. I mean we sh...

Thank you for your reply. I made my step size smaller but the problem still exists!! (First my step size was 0.001 and I made it 0.0001 but ...). As I told you before, this algorithm worked for a 3D smaller structure (2 story building) but for 6 story this problem exists. I think my section definiti...

Hi I am modeling a six story building and I want to perform some pushover analyses. But while doing the pushover analysis, I faced these errors : WARNING - ForceBeamColumn3d::update - failed to get compatible element forces & deformations for element: 60100(dW: (( 4.76821e-012, dW0: 6.06719e+028...

HI,
Thanks for you reply. But I couldn't understand your point! what do you mean by "a file from the other program"?! I'll be really thankful if you explain it a little bit more!
Thank you very much!

Hi I am working on 3D models in opensees. I just want to know that if there is any way to make an output for opensees in matlab or vice versa! I have to perform some 3d analysis which is very hard by opensees, so I wanted to use matlab instead and see that if it is possible to relate these two (Matl...