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There are non-soil materials in NDMaterial, e.g. J2 plasticity model for metals. For the soil models some tensile load is allowed, if the soil has some cohesion which can be specified in the multi-surface model and the Drucker-Prager model in OpenSees.

I located where the warning "nDMaterial: MyModel could not be created" is. It's in the file TclModelBuilderNDMaterialCommand.cpp (Line 1001). It appears that the section corresponding to dynamic API for nDMaterial is not implemented yet. I checked the repository to see if I have the update...

Frank, I have created the DLL successfully, and while running the input tcl file I get a warning that nDMaterial could not be created. All the files are in the same directory, and there are no mismatch of names. I'm not sure if the problem is because OpenSees during execution doesn't recognize the m...

Frank, I resolved the link error. I needed to set the path properly for the library file. The dll is created successfully. However, I am getting the following warning: Linking... Creating library C:\OpenSees\OpenSees\PACKAGES\NewMaterial\fortran\elasticppf.lib and object C:\OpenSees\OpenSees\PACKAGE...

Hi Frank, Now I have the latest version of Intel Fortran compiler and am able to open the example fortran project. I tried to build it, but got a linking error that has to do with 'minPackageC.lib.' I located the file, and added it to the source. Then I rebuilt the project and got the same link prob...

In the laboratory triaxial test during the consolidation stage drainage is allowed from the top and bottom of the specimen (two-way drainage) by opening the valves. The excess pore pressure is allowed to dissipate. During the shearing stage (say CU test) the valves are closed before applying the dev...

Thanks, Frank. I got it to work.

I don't think you are simulating a cyclic CU test if you are applying motion at the base. You should be applying cyclic deviatoric stress at the top surface of the specimen after the isotropic consolidation step. The consolidation step is done under drained condition while the shearing step is done ...

I don't think there is a command to get the nodal stresses in OpenSees. You could write a short script in Matlab or any programming language of your choice to compute nodal stresses from the gauss point stresses (stress smoothing approach). For a linear quad element with simple shape functions it is...

Hi all, I'm trying to apply cyclic load (constant amplitude) via a Trig Series in a transient analysis. The analysis runs but it appears that the cyclic load is not applied because the the displacements, stresses and strains are same as at the end of the previous analysis. The cyclic step is as foll...

It appears that there are several commands that are implemented in OpenSees that are not mentioned in the manual. When should we expect an updated manual?

Is there a getStrain command or is it a function in the material implementation code? If such command exist is there an example on how to use it. If no such command exist, is there a command to extract strain component during the analysis to check the values rather than from the output files.

I use WinCVS so I don't know how similar it is to tortoise CVS. Initially, I got a similar problem with the connection failure. I realized that I skipped the colon in front of pserver in the CVSROOT. Once I fixed it, OpenSees is checked out fine. So make sure you are not leaving out or misspelling a...

Thanks for your response. The example project was created using a higher version of Intel compiler. The one that I have is 9.1 so I can't open it. Anyway, I created a new project with the Dynamic-link Library template. Then added subroutine elasticPPf, materialTypes and materialAPI modules in the so...

Hi Frank, The example VS project to create the dll (WindowsDLLs) is for c and c++. I have a Fortran source file for the material model, and also the Fortran compiler. I need to add materialTypes and materialAPI modules in the source folder along with the user material subroutine which uses them. Is ...