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Did you try it? Please give it a try as I know cases that it worked just fine.

If the truss method works for your case and your results are good, you should proceed with that. You don't need to necessarily use the equal dof constrain in the axial direction.

To explore the issue with the equal dof solution, what is the constraints handler that you are using?

You can divide your element into several elements and assign different sections (or I and A depending on the element that you use) to each element. If you use enough number of elements, you can have a good enough approximation.

You can use the force recorder to record all forces of the zerolength element. Below is an example:

recorder Element -file name.out -time -ele 11 force;

Please check the list of available NDmaterials from the link below and see if any of them is useful for your purposes.

http://opensees.berkeley.edu/wiki/index ... al_Command

You can try displacement-based elements instead of the force-based elements for the walls. However, in this case you should use more than one element (probably 4 or 5) for each wall. Since the displacement-based elements do not require an iterative element formulation, you can improve convergence fo...

Does the second solution (the one with the truss) work properly for your 3D model?

A more straightforward way to make this check can be: Change the materials to elastic materials and increase the number of fibers (30x30 for example). Check if the recorded stress at a particular location is equal to the theoretical value from s=My/I. If this equation holds correctly, there may be o...

You can find an example adaptive script below. You may need to make some modifications to fit it into the rest of your script. set Tol 1.0e-8; set maxNumIter 100; set printFlag 0; set NewmarkGamma 0.5; set NewmarkBeta 0.25; set TestType EnergyIncr; set algorithmType NewtonLineSearch; for {set ik 1} ...

There are different methods in literature to model steel shear walls. What are you using in your case, trusses?

Please see the below reference for investigation of the effect of convergence tolerance on several response parameters of bridges. In that paper 1e-5 is observed to be adequate for energy norm. However, the best strategy is to start with a small tolerance like 1e-8 and try iterations with increasing...

Yes it is possible to output curvature using the section deformation recorder. An example is provided below:

recorder Element -file ele1sec1Defo.out –time -ele 1 section 1 deformation

Please check http://opensees.berkeley.edu/OpenSees/user/download.php for downloading OpenSees and installing tcl.

You can find many tcl file examples in

http://opensees.berkeley.edu/wiki/index ... les_Manual or
http://opensees.berkeley.edu/wiki/index ... les_Manual

Please see the explanation provided by the user ndao.

You can simulate global buckling using corotational transformation and a small initial offset in the middle of the element (could be 1/1000 of the element length).

http://opensees.berkeley.edu/wiki/index ... sformation