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I recently built two frame models with concentrated plasticity represented by one zeroLengthSection element at each end. The rigid zone are simulated by several elastic elements with a common joint. One model is one story, it runs ok! However, when the model is extended to 2 stories, something stran...

Sorry made a mistake, the source file should be: ------------------------ ##### ----- External functions ----- ##### proc BoxSec {secID matID d b tw tf nfdw nftw nfbf nftf} { set dw [expr $d - 2 * $tf] set bw [expr $b - 2 * $tw] set y1 [expr -$d/2] set y2 [expr -$dw/2] set y3 [expr $dw/2] set y4 [ex...

I recently made a model representing a generic frame connected with a piece of rocking column by rigid links. This model is first pushed to 465 mm by displacement control, which runs very well. Then it is released by "remove LoadPattern" command to simulate the vibration. The dynamic analy...

I checked the source code of OpenSEES and found there is a class for EnvelopDrift recorder. I tried, but failed. Does it mean this capability is not integrated, or my usage is not correct? If the capability is integrated, could anyone give me the instruction of the usage of this recorder. Thanks in ...

I get a problem when doing 3D pushover analysis. I try to push the structure to the positive direction. The result however shows a positive displacement with a negative force. I don't know whether I defined the pushover analysis wrong or not. I would appreciate if anyone could help me figure this ou...

Dear all: In the example 5, when I change the elastic section of all girders to fiber section involving nonlinearity, error occurs. The given hints are: "WARNING - ForceBeamColumn3d::update - failed to get compatible element forces & deformations for element: [ele no.](dW: << -1.#IND, dW0: ...

If only analyzing five steps (0-0.05), the result of reaction force on node 3 is correct. But if analyzing six steps (0-0.06), the reaction force on node 3 is not correct, and the displacement on this node is not the displacement assigned to it. Can anybody check it? or is my syntax incorrect? Thank...

The first five steps work fine. But after six steps, I checked the displacement of Node 3, and found it's zero. I don't know why. Can anybody help me? Thanks alot. model basic -ndm 2 -ndf 3 node 1 0.0 0.0 node 2 0.0 3.0 node 3 0.0 4.5 fix 1 1 1 1 fix 2 0 1 1 fix 3 0 1 0 mass 2 100000.0 0.0 0.0 geomT...

When doing restart analysis, the loadpattern of previous analysis works
or not in the current restart analysis?

Can I remove the loadpattern of previous analysis before the current
restart analysis? and how?

Thanks in advance.

Hi, Silvia:
I think I have solved the problem.
Thank you for your suggestion.

Sorry, I cannot understand your question.
The recorder has no effect on the analysis. In fact, I check
the result by "print".
If you run the code, please delete the two recorder lines.

Thank you very much.

Thanks for your reply. I tried "imposedMotion" command, but found the result still no change: the velocity and acceleration are still zero. I don't know why? is there anything wrong in my code: model basic -ndm 2 -ndf 3 node 1 0.0 0.0 node 2 0.0 3.0 fix 1 1 1 1 mass 2 64.0 0.0 0.0 geomTran...

I want to apply acceleration on one node with mass or without mass.
Can I do it in OpenSees
Thanks

Frank, thanks for your reply. It still cannot work. I checked the boundary acceleration and velocity, and found both are zero. Therefore "reactionIncludingInertia" cannot work. I think the critical point is: how to handle "sp" command in dynamic analysis. I think in the current v...

And the reason may be the definition of :

#IPE270
section Elastic 1 $E $A1 $Iz1 $Iy1 $G $J1
#IPE330
section Elastic 2 $E $A2 $Iz2 $Iy2 $G $J2
#TUBO260x10
section Elastic 3 $E $A3 $Iz3 $Iy3 $G $J3


I didnot do the analysis, but I cannot found where you define nonlinearity.