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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: to get results in this order: If I use ShellMITC4 and PlateFiber, like this: I have all results as zero for: since "material 1" is misleading I suppose...

I have 24 results (6 forces/moments by 4 GPs) for: I cannot still obtain the generalized shell forces Nxx, Nyy, Nxy, Mxx, Myy, Mxy, Vxz, Vyz.
How the recorder should be written in order to get such forces per unit lenght? They should be 8 x 4GPs.
To clarify, I'm not looking for single-fiber stresses. Thanks in advance

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 fmk to include this software in the Tools page (http://opensees.berkeley.edu/OpenSees/user/tools.php) if possible; below a short description:

NextFEM Designer is a user friendly Finite Element Analysis program, which can be used alone or to be a pre- or post- processor for several widely used FEM programs (i.e. OOFEM, SAP2000, Midas GEN, OpenSees, ABAQUS/CalculiX, Zeus-NL, and others).
List of features:
- general pre-processor capabilities: 3D and 2D views, customizable colours, accelerated rendering with DirectX technology;
- modelling with the most common structural elements, such as beams, shells and solid elements;
- importing input files from DXF drawings, OpenSees scripts, Midas GEN, SAP2000, ABAQUS, OOFEM, Zeus-NL;
- importing results from SAP2000, OOFEM and OpenSees;
- exporting models to SAP2000, ABAQUS, Midas GEN, OpenSees, OOFEM;
- post-processing capabilities with deformed shapes with contour display, beam diagrams, stress and strain contour.

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

The point was the name of the libs. It is necessary to publish some instructions on the wiki.

dear fmk,
thanks for your reply. However, it seems harder that described. As I said, I got mumps (and blacs) and scalapack for windows, but the referenced LIB files in OpenSeesSP and MP projects are not so clear. I found:
blacsCinit_MPI-Win32
blacs_MPI-Win32
scalapackd
mumpsFortran
mumps

Can you provide a short description for each of them? I can compile the version required of MUMPS (4.7.3) and I think I'm getting the same libraries but I need to know what is inside each of them in your original compilation.

Moreover, SuperLU_distrib must be compiled from the files in OTHER\SuperLU_DIST_2.5 or OTHER\SuperLU_DIST_2.0 ?

Thanks a lot,
Giovanni

There is not what I intended. An API allows you to call the function inside OS.

Sap has APIs for Vba.
Can the opensees apis be called from vba or .net?

Dear fmk,
thanks for your reply. I could agree with that, but I cannot share the reasons. I lost more than one month to catch this error and as I said, the comparison with other solvers (such as Abaqus and SAP) didn't help too much because they automatically correct these errors (that, let me say, are triavial in a large mesh!).
From this forum I noticed that the same error can be raised from an incorrect node numbering in element (as you reminded), I wrote a code that checks for counterclockise connectivity but it was not the solution for me (and the OS error in my opinion had to be different from the case of free nodes).

So, in these cases a warning can be useful to help users to know what's happening; otherwise, handling large models can be very difficult in OS.