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1) A FIBER BEAM-COLUMN ELEMENT FOR SEISMIC RESPONSE ANALYSIS OF REINFORCED CONCRETE STRUCTURES by Fabio F. Taucer, Research Assistant, Enrico Spacone, Doctoral Student and Filip C. Filippou - Associate Professor Report No. UCB/EERC-91/17 Earthquake Engineering Research Center College of Engineering ...

Thanks a lot !
I tried it - but it shows the message:
"More than 25 iterations in constituive subroutine J2-plasticity "

Hi,
Can somebody tell me about the parameters in J2 plasticity.
nDMaterial('J2Plasticity', matTag, K, G, sig0, sigInf, delta, H)

What are delta and H ?
How to calibrate them from experimental stress-strain curve ?

Lapack errors are because - there is some discontinuity in your model or no proper support i.e. your model is moving as a rigid body

Hi, In the GitHub source of elasticBeamColumn3d, I see implementation of moment releases. Are they exposed to interpreters ? OpenSeesPy documentation talks only about 2d case. If anybody has used them in their local compilation, can you please tell me if they are working properly? What does 0,1,2,3 ...

I think you should also fix out of plane DOF for 3-D truss elements.
For example if the pushover load is in x-y plane the for truss end nodes the fixity should be - fix(0,0,1,1,1,1) - arrest z movement
if the load is in x-z plane then fixity should be - fix(0,1,0,1,1,1) - arrest y movement

Sorry sir,
Problem solved. The "-" before the "-disp" caused the kernel to be dead. Now its working.
The correct command is:
ops.recorder('Node','-file','disp.txt','-node',2,'-dof',1,'disp')

Dear Prof.Scott, This is just the python version of the uniaxial material test https://opensees.berkeley.edu/OpenSees/manuals/usermanual/751.htm?fbclid=IwAR0cGjrGz2coyudp3v90Ly8Qz33HGd0cj02leHGnGl-ChB_Lf3Q8uvDfkvo The pattern cab be found in the same link (first line of the code). This is the code i...

I am using node recorder as "ops.recorder('Node','-file','disp.txt','-node',2,'-dof',1,'-disp')" If I comment out this line code runs properly, but if I include this the message shows up - "kernel dead...."___"Restarting kernel".. Did anyone face this issue..? Can you h...

Can you include that effect in your material model ?
As far as my understanding goes with OpenSees - it is strong in material modelling. So when using OpenSees always think - can I convert this phenomenon into a material model..? At least I tend to think like that - personally.

I think yes. You can give very small rotational stiffness...

Instead of going for two elements - I think it's better to go for two materials in a same beam element cross section. This is possible using fiber section. https://opensees.berkeley.edu/wiki/index.php/OpenSees_Example_9._Build_%26_Analyze_a_Section_Example See this presentation for visualizing a com...

Sorry, here is the image
https://drive.google.com/file/d/1tvaq2V ... sp=sharing

Dear Prof. Scott, One more question. After formulating the material and running the test analysis( https://opensees.berkeley.edu/OpenSees/manuals/usermanual/751.htm?fbclid=IwAR3TT7NnC8HvDKVz9Rkko-dOlB33o7VfJOGa9frFfmLwumeFpU8yPeZbHdU ) - I am getting a plot like shown in the figure. Everything is fi...

Thanks a lot. It worked.