We introduce the concept of field consistent representationudof continuum problems in structural mechanics whichudrequire definition by more than one field variable. Inudsome practical situations, the engineering dimensions ofudthe problem require that the many field variables neededudto model the deformation of the continuum may have to beudconstrained among themselves in a suitable way, If thisudis not properly accommodated in the finite element model,udsevere errors can result. Here, we consider a new terminology for such errors and examine a simple case in which such errors can lead to the locking phenomenon, Techniques, most of which originated on an ad-hoc basis even before the mechanics of field-consistency was established, can now be re-interpreted to show how they successfully introduce a consistent representation of the constrained strain-fields and thus remove the 'spurious constraints' that lead to 'errors of the second kind'.
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