Usermat in ansys/ls-dyna HOW TO?

[frangibolt]

Hi, I have to implement a material model in ansys/ls-dyna using the usermat subroutine. The problem is that I don't know how can I do this. Is there a tutorial or a guide that explains in a simple way how to implement user-material?
How should I use usermat.f and dyn21.f?

Thank you very much, I am a bit afraid about using usermat..

[Jorgen]

I know of no simple tutorial - it is not easy to write a user-material subroutine :o

I recommend that you read the user's manuals carefully and do it step-by-step.

-Jorgen