Dear Ahmad,

If my inference is right about your question, This will be my suggestion:

you may write your user material programs in two separate user subroutines (which are not UMAT or any other subroutines provided by ABAQUS). Then you can call them into UMAT appropriately depending on the governing conditions (conditional statements). Now, SDVs could be updated from 1 to 15 (as what you explained for an example) accordingly.

Hope this will be of use.

Hi Ramin,

Thanks for your response. You mean I should not combine the the sub-UMAT's in a single one. So, how can I call them inside the UMAT? Is it possible to "call" a separate subroutine inside the UMAT?How?

Cheers,

Ahmad

Dear Ahmad

You can give a number for Depvar and that is the number of SDVs you can use in the umat or vumat. Just assign a parameter for State variable with a special number (1,2,3...).

For the other question yes you can have a subroutine inside subroutine. Just write the other subroutine after the first  one finished with END and call the second subroutine inside the first  one  when you  need  it.

Cheers

Hi Shahram,

Thanks. 

I could handle it :) but there were several fine points!

Cheers,

Hi Ahmad,

you can call your own subroutines into UMAT by the command "call".

For more information you are advised to refer to the existing examples in ABAQUS documentation or any other on the internet.

By the way, I was wondering if you could tell a bit about what you are trying to model?

Cheers,

Hi Ramin,

I am modeling damage in textile composites (both in yarns and matrix) using mesh super position technique. In few papers of mine, you can follow the concept. For more detailed responses, please feel free to ask me.

Regards,

Hi Ahmad:

     There is a character variable in UMAT arguments called CMNAME.  This brings in the name of the material in your "Materials" list in CAE.  Use this as a flag to distinguish which material is this element, then with either an IF statement within a single UMAT subroutine or by having KSUB1 for material 1 and KSUB2 for material 2, you can save the SDVs for the corresponding material.  You can call any number of subroutines with in UMAT but all this should be in one file for compilation.

You can have any number of materials in UMAT just distinguish them with an IF check and appropriate sections of the coding accordingly.

Can any one define waht is "DEPVAR" in abaqus?

Dear Aala Satyanarayana

This keyword is used to define the number of internal state variables for a user-defined material. They are initialized to zero at the start of the calculation and can be used within a material user subroutine.

Hello

Can any one gives me an interesting documents for writing UMAT

Regards