Random variations of material properties in CAE?

[rmettier]

Hi

I'm using Explicit to model some geodynamic stuff, and I've reached the point where perfectly homogeneous materials are becoming a problem. What I'd like to do is have an elastic definition for, say, granite with (E=53GPa, v=0.28) and then add a small random deviation to Youngs modulus (maybe +/- 2%) for each element.
Is there a way of doing this in CAE, or any other way for that matter?

 

[loki3000]

i'd say UMAT/ VUMAT

 

[rmettier]

Hmmm, that's what I dreaded.
I've spent quite a while trying to understand the example for UMAT in the manual, and I'm afraid it's simply gibberish to me.

Isn't there some way of assigning materials to element sets directly? I ask because it's fairly easy to modify the input file to divide the elements into randomly selected sets. I could then assign slightly different materials to those sets.

 

[brep]

You can do it in Abaqus/CAE with its support for discrete fields. This was first supported in V6.7EF or so... There should be examples in the manual.