In Abaqus UMAT, is DDSDDE the same with "effective deviatoric elasticity"?

Hi all,

In Abaqus Theory Manual 4.6.1, there is a concept called "effective deviatoric elasticity". I think that term is actually DDSDDE, i.e. the consistent linearized tangent moduli. 

But why is it called "effective  DEVIATORIC elasticity"? It sounds like we missed the volumetric part (but only considering the isochoric part).

I would really appreciate it if someone could help me with this. Thanks!

-Shawn