Multiple Material Directions

[zeroplus]

So I am working in ABAQUS Standard, simulating an anisotropic material that requires a user subroutine.

The subroutine and simulations all work okay, lining up with analytical solutions to the problem with the same material model. However, the project is moving on where we are going from 2 fibers in our material to 3,4 or even 5 fibers, all at different orientations on a shell structure. I know ABAQUS has a limit of 3 defined material directions but is there a way to get around this or define it +3 specifically for anisotropic materials?

For example, when defining a hyperelastic material property in ABAQUS, if an anisotropic material that is user defined with invariant formulation there is an option to set the number of local directions. This can be increased to a maximum of 6, which is contrary to the 3-limit described in documentation. Is this just a bug?

I am pretty sure 3 is the hard limit but I would interested to hear what insights people have.

 

[FEA way]

What kind of material do you want to model ? For example, is that a fiber-reinforced polymer ? Depending on that, maybe you could use a different modeling technique.

Which version of Abaqus do you use ? Is the documentation referenced by you related to that version of Abaqus ? Some limitations were changed in newer releases.