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I had a look at GroundMotion.cpp, the function GroundMotion::getVel does not account for velocity response.
However, it is not clear to me if I can implement the velocity output using numerical derivation over time.

Hello, please find attached a minimal working sample based on the damper TCL example on OS wiki. Analyses compared: - UniformExcitation, null accel and vel on output, base node displ are zero (UE series in plots) - MultipleSupport with accel TH applied ("clean" tag in plot, as quantites ar...

Which Transformation constraint handler do I have to use?
As by preceding post, it seems all of them lead to the same result.

yes, constraints Transformation, but I get zero accel and vel also with Plain and Penalty (Penalty gives nearly 0 at constrained nodes).
Lagrange gives error if no alphaM/S are specified.

Hi all, I've a model in which I imposed the displacements to the ground (in order to simplify, in this sample I used the same TH): From: https://opensees.github.io/OpenSeesDocumentation/user/manual/model/multiSupportPattern.html I read: The results for the responses at the nodes are the ABSOLUTE val...

I think I found the point - theElement->strain was always zero, due to the fact that does not set any trial strain on the element.
I used this because at this stage my model is linear, anyway I turned into and now I have forces.

Hello, I read here that one can use: recorder Element -file ele1gp1forces.out -time -ele 1 material 1 forces to get results in this order: [Time Nxx, Nyy, Nxy, Mxx, Myy, Mxy, Vxz, Vyz] If I use ShellMITC4 and PlateFiber, like this: nDMaterial ElasticIsotropic 3 210000 0.3 nDMaterial PlateFiber 2 3 s...

cromance wrote: > Is there anyone who use this dll for response spectrum analysis? > I can't perfrom eigen value analysis with pFactor command using Opensees > 2.5.0. Please tell about the error encountered. The DLL was updated a few months ago. If you can, uploading your model will be of great help.

Hi everyone,
can OpenSees perform linear stability (buckling) analysis?
I cannot find any reference on that, and I've never seen any geometric stiffness matrix in the elements' code.

Thanks

I'm trying me too, but I get an overflow error when trying to read "theParam" array. It seems that the c_f_pointer it's not working.
Moreover, you must correct the "if results != 1" in TCLelement_api in "if results != 0".
Still looking to solve...

Thanks

Dear all, it is available from now a brand-new software that supports, amongst the other features, pre- and post- processing for OpenSees. Some applications will be presented in the upcoming OpenSees Days Italy in Salerno. It can be downloaded from http://www.nextfem.eu and it is free. I kindly ask ...

Deaf fmk,
is there an example for ms visual studio on how to compile a new system as external DLL?
if not, can you tell me please which template I can use (maybe the one for the new element or for newCommand)?

thanks in advance,
Giovanni

got it, it's clear now.
Thanks

Dear fmk,
what is exactly the difference between OPS_GetNodeIncrDeltaDisp and OPS_GetNodeIncrDisp in the element APIs?

thanks,
Giovanni