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Hi , I have a question about Fix command. I have some nodes in my model that I need to set them fix for gravity analysis and then in the same tcl file set the same nodes free for dynamic analysis for some Dofs. I wonder if there is any command that I can use to remove their constraint. for example: ...

Hi, Does anybody know how lagrang multiplier nodes work in BeamContact elements? and How I can define them? I saw the Excavation example in OpenSees. All the lagrang multiplier nodes have the same coordinates (0,0) in 2D ,and I can not realize the concept behind that. Thank you so much for your help...

Hi Frank,
I have the same problem. I switched to hansen resource option. But my status is always "Submited" and it does not start running. Do you have any suggestion?
I am using opensees SP so I just changed the System command to System Mumps.

Thank you so much for your help,
Bahareh

Thanks for your help. it works:)

Hi, I have problem with recorder command.I have 2000 nodes and I want to record each node displacement in separate file . I used the for loop and recorder command to create 2000 files, but I can not have more than 300 files. I can have 2000 files if I used nodeDisp command. But I do not know if I ca...

Hi, I am trying to using EqualDOF between the soil nodes and the pile cap nodes.My soil elements are brick so they have only 3DOF and my pile cap is frame so they have 6DOF. when I use EqualDOF in z direction after getting the result, node displacements are not the same in Z direction and displaceme...

Thanks for your reply. Yes you are right some of the NDmaterial are not only for soil. I am using nDMaterial PressureIndependMultiYield which is only for soil. Does it also work in tension??? Because I am trying to connect my pile cap to the soil with using Equal degree of freedom command in z direc...

I also want to know how I can see the source code for these type of materials in Opensees. I appreciate if someone can help me with that.

Hi,
I was wondering if anybody knows that ndmaterial in opensees works only in compression or both tension and compression. I know these material are for the soil modeling and soil just works in compression. But I just want to make sure about it.

Thanks,
Bahareh

Thank you for your reply. I assigned mass only to the node on the top of the column.My mass command is:

mass 8 $mconc $mconc $mconc;

Do you think this error can happen because of using metric units?

Thanks

I am trying to model pile , pile cap and column in 2D. I got the T for static analysis but in dynamic part he gives me this type of error: ArpackSolver::Error with _saupd info = -1 N must be positive. WARNING DirectIntegrationAnalysis::eigen() - EigenSOE failed in solve() missing function argument a...