A field-consistent formulation for the eight-noded solid finite element

Abstract

A field-consistent eight-noded displacement type solid element is derived by augmenting the usual eight trilinear shape functions with bubble functions and smoothing to achieve consistent definitions for the constrained strain fields. This produces an element that is free of parasitic shear and 'Poisson's locking' and is now also frame invariant, i.e. the element stiffnesses are invariant regardless of the node numbering scheme or the orientation of the element local axes system. The field-consistency approach is also used to free the element of locking in the incompressible/near-incompressible regime.