High-Order Analysis of Unidirectional Sandwich Panels with Piezolaminated Face Sheets and Soft Core

The bending behavior of unidirectional sandwich panels ("wide" or "narrow" beams) with a compressible "soft" core and piezoelectric active face sheets is investigated. The panels studied consist of composite face sheets with embedded active piezoelectric layers and a compressible core. The mathematical formulation adopts the principles of the high-order sandwich panel theory. The field equations and the boundary and continuity conditions are derived through the variational principle of virtual work, and the electromechanical effect is introduced using the linear piezoelectric constitutive equations. Higher-order effects due to flexibility of the core are incorporated in the analysis as a result of the solution of the field equations and are not presumed a priori. Numerical results are presented for typical cases of active sandwich panels and the effectiveness of various electrical actuation schemes is investigated. The effects associated with using piecewise continuous active layers are also investigated and discussed. The results reveal the capabilities of the proposed model and highlight some of the problems involved with the analysis and design of active sandwich panels. (Author)