Windows Environment for User Programmable Features

As soon as Abaqus/CAE starts, it creates a file called abaqus.rpy on the Abaqus default directory. By locating this file you will know which is the Abaqus default directory in your installation.

When Abaqus starts, it reads the file abaqus_v6.env from c:\simulia\abaqus\6.xx\site. To enable F90 functionality, copy the file abaqus_v6.env to the Abaqus default directory. Then, edit the copy of abaqus_v6.env to add the keyword '/free' to the compiler directive, as shown below. It is best to add '/free' to your own copy of abaqus_v6.env--do not replace the compiler directive with the example line below, ad '/free' to the compiler directive on your copy of abaqus-v6.env.

compile_fortran=['ifort', '/c','/DABQ_WIN86_64',
                 '/recursive', '/Qauto-scalar', '/QxW', '/nologo', '/Od', '/include:%I', '/free']

For Abaqus to accept user code, you must have Intel Fortran 11.1, and the Visual Studio (VS) 2008 shell that comes with it, installed. The VS 2008 shell that comes with Fortran 11.1 is all you need but having the full VS 2008 adds functionality. If you want to use the full VS 2008, you have to install VS before installing Fortran to get Fortan integrated into VS. In either case, you must upgade VS 2008 to SP1 or better. The upgrade is free and available on the web. 

Next, add the following 2 strings to the ABAQUS command file (C:\SIMULIA\Abaqus\Commands\abq6102.bat)

call "C:\Program Files (x86)\Microsoft Visual Studio 9.0\VC\bin\x86_amd64\vcvarsx86_amd64.bat"
call "C:\Program Files (x86)\Intel\Compiler\11.1\065\bin\intel64\ifortvars_intel64.bat" vs2008
right above the existing strings
@echo off
"C:\SIMULIA\Abaqus\6.10-2\exec\abq6102.exe" %*

These 2 strings correspond to the Win7x64-bit platform. They might be different for other platforms such as Win7-ia32, and so on, but the .bat files have similar names and you can find them in your system, then modify the strings to point to them. 

Using VS 2008, you should debug your UMAT before trying it out with Abaqus. A simple umat_tester.f90 is avalable in \cite{feacm-abaqus} to help you. You can modify it to suit your needs. 

Once you modify the compiler directive, UMAT code can be written in F90 format, as long as the file name given to Abaqus has an extension .for. Since F77 is very limited, I prefer to use F90. Unfortunately, Visual Studio requires F90 code to have an extension .f90. Therefore, once the .f90 code is debugged, you have to copy it to a file with extension .for. 

UMAT, VUMAt, UGENS, and UEL examples in Abaqus documentation are writenn in F77. A free converter, written in F90, is available in \cite{Metcalf}, mirored in \cite{feacm-abaqus}.


[Metcalf] Michael Metcalf, A tool to convert f77 source code to f90, ftp://ftp.numerical.rl.ac.uk/pub/MandR/convert.f90