I am starting off with an attempt to code up a basic user element (the same as a 3D 8-noded brick element in a UEL.
I have a few questions:
Do I have to include shape functions in my coding?
Do I have to include Gauss Quadrature in my coding?
Is there any way to view an example 3D element formulation for abaqus? (any references)
I will start from here, and eventually lead to a reduced stiffness matrix formulation, similar to hybrid element. (this is for dof reduction, not for incompressibility, though I will have to incorporate incompressibility as well)