Anisotropic Elastic-Viscoelasticity

Hi,

I am looking to model anisotropic viscoelastic behaviour of fibre composites. Since, there ABAQUS doesnt support this model I am looking tips of writing UMAT for this particular model. I have gone thorough formulations of three dimensional viscoelasticity(Kaliske 2000) but its numerical implementation is not clear. Moreover, I am unsure which subroutine will help me model this for frequency dependent behavior for use in steady state dynamics step in ABAQUS(UEL doesnt seem to be called by ABAQUS for steady state analysis).

Many Thanks,

Mehtab