This paper proposes mixed finite elements, FEs, with an
apriori continuous transverse electric displacement component
. The
Reissner Mixed Variational Theorem (RMVT) and the Unified Formulation
(UF) are applied to the analysis of multilayered anisotropic plates with
embedded piezoelectric layers. Two forms of RMVT are compared. In
a first,
partial, form (P-RMVT), the field variables are displacements
, electric potential
and transverse stresses
. The second,
full,
form (F-RMVT) adds
as an independent variable. F-RMVT allows the
a priori and complete fulfillment of
interlaminar continuity of both mechanical and electrical variables.
We treat both equivalent single-layer models (ESLM), where the number of
variables is kept independent of the number of layers, an layerwise models (LWM), in
which the number of variables depends in each layer. According to the UF the order
of the expansions
assumed for the
,
,
and
fields in the plate thickness
direction
as well as the
number of the element nodes
have been taken as free parameters.
In most cases the results of the classical formulation which are based on Principle
of Virtual Displacements (PVD) are given for comparison purposes. The superiority
of the F-RMVT results, with respect to the P-RMVT and to PVD ones, is shown by
few examples for which three-dimensional solution is available. In particular, the
F-RMVT results to be very effective for the evaluation of interlaminar continuous
fields.