An analytical solution is presented to determine the interlaminar stresses at the free edges of long symmetric cross-ply laminates with piezoelectric material properties subjected to uniform extension in the length direction. The displacement field is assumed within the framework of a second-order shear deformation theory. Also the electromechanical coupling is considered and it is assumed that the electric potential varies linearly through the thickness of the layers. Using the principle of minimum total potential energy, equilibrium equations are obtained in terms of stress, moment, and electric flux resultants. The coupled three-dimensional constitutive equations of piezoelectricity are considered. Finally, a set of ordinary differential equations with constant coefficients are obtained. The solutions of the equations are the unknown assumed functions for displacement field and electric potential. The numerical results obtained from this theory are compared with those obtained by other investigators and finite element method. Numerical results clearly indicate the singular behavior of interlaminar normal and shear stresses in the boundary-layer region of the laminate.

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