Analysis of piezoelectric bimorphs and plates with segmented actuators

Elastic plates with distributed or segmented piezoelectric layers have been analyzed using the classical laminated plate theory, the first-order shear deformation theory, and the results are compared with an analytical soluti on. The plate theories and the analytical solution take into account both t he direct and the converse piezoelectric effects, and assume generalized pl ane strain deformations. The transverse displacements from both theories ar e in reasonable agreement. The classical lamination theory gives a disconti nuous longitudinal stress at the edges of the segments whereas the analytic al solution predicts a continuous curve with steep gradients. Piezoelectric bimorphs with the axis of transverse isotropy inclined at an angle to the thickness direction are also studied using the three formulations. The disp lacements and stresses obtained from the first-order shear deformation theo ry are in very good agreement with the analytical solution even for thick p lates. It is advantageous to use shear bimorphs since the stresses induced in them are smaller than those in extension bimorphs. (C) 2001 Elsevier Sci ence Ltd. All rights reserved.