Active control of laminated composite beams using a piezoelectric fiber reinforced composite layer

The effectiveness of piezoelectric fiber reinforced composite (PFRC) material in the development of new actuators as elements of smart structures has been theoretically investigated. The piezoelectric fibers considered in this study are longitudinally oriented to yield the bending mode of actuation. Micromechanics is used to predict the effective mechanical properties and the effective electromechanical constant of such composites which gives rise to actuation in the fiber direction when subjected to an electric field transverse to the fiber direction. These effective properties are useful for the analysis of smart beams. A micromechanics study reveals that beyond a critical fiber volume fraction, this electromechanical constant is improved over that of the piezoelectric material alone. The performance of this new material used as distributed actuators has been investigated through active constrained layer damping (ACLD) of laminated composite beams in which the constraining layer is made of piezoelectric fiber reinforced composite. A finite element model has been developed to describe the dynamic behavior of a laminated composite beam coupled with active constrained layer damping (ACLD) treatment. The controlled response is illustrated through plots of frequency response functions. The results indicate that these new piezoelectric composites may be superior candidate materials for use in developing lightweight smart structures, as compared with the existing piezoelectric materials alone.