On functionally graded beams with integrated surface piezoelectric layers

An exact analysis based on state space formulation is presented to study functionally graded beams integrated with surface piezoelectric actuators and sensors. The bonding adhesive between the host beam and the piezoelectric layers is modeled by a spring layer in order to consider the effects of adhesives. Different parameters of models of spring layer correspond to different bonding conditions, either perfect or imperfect. Both the host elastic functionally graded beam and the piezoelectric layers are orthotropic and in a state of plane stress, and the former is inhomogeneous along the thickness direction. A laminate model is employed to approximate the host beam. Numerical examples are presented and significant results are adduced and discussed to illustrate the effect of bonding conditions.