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Static analysis of laminated smart composite plates integrated with a piezoelectric fiber, reinforced composite PFRC) layer acting as distributed actuators has been carried out by a generalized-energy-based finite element model. A simple first-order shear deformation theory is used for deriving the model. Eight noded isoparametric serendipity elements are used for discretizing the domain. The performance of the PFRC layer has been investigated for both symmetric and antisymmetric cross-ply and antisymmetric angle-ply laminated composite shell substrates. The effect of piezoelectric fiber orientation on the control authority of the PFRC layer has also been studied. [ABSTRACT FROM AUTHOR]

A novel work demonstrates the effect of delamination in smart laminated composite beams on the performance of active constrained layer damping (ACLD) treatment. A finite element model has been derived to formulate the dynamics of the composite beams integrated with a patch of ACLD treatment and a patch of piezoelectric film acting as a distributed sensor with and without the presence of delamination at different locations. Frequency response functions of the beams have been examined to observe the effect of delamination on the performance of ACLD treatment. It has been observed that the ACLD treatment improves the active damping characteristics of the beams, even in the presence of delamination, and that the responses of the beams are sensitive to the variation of the location of delamination. The responses due to active constrained layer damping presented may provide a useful guide to detect the presence of delamination in smart composite beams by the use of the existing numerical techniques. [ABSTRACT FROM AUTHOR]

A simple method for optimal control of vibrations of simply supported thin laminated shells integrated with piezoelectric layers is presented. The piezoelectric layers act as the distributed sensors and actuators. Coupled electromechanical governing equations of motion are derived using Hamilton's variational principle. The algorithm for a linear quadratic regulator with output feedback has been employed to formulate the optimal control problem. Controlled responses for various design parameters are illustrated, and a study of the effect of variation of the central angle subtended by the shell on the performance of the actuator is presented. [ABSTRACT FROM AUTHOR]

The effective coefficients of piezoelectric fiber-reinforced composites (PFRC) have been determined through micromechanical analyzes. The method of cells (MOC) and the strength of materials (SM) approach have been employed to predict the coefficients. A constant electric field is considered in the direction transverse to the fiber direction and is assumed to be the same both in the fiber and the matrix. MOC and SM predictions for the effective piezoelectric coefficient of the PFRC assessing the actuating capability in the fiber direction are in excellent agreement. It has been found for the piezoelectric fibers considered that, when the fiber volume fraction exceeds a critical fiber volume fraction, this effective piezoelectric coefficient becomes significantly larger than the corresponding coefficient of the piezoelectric material of the fiber. The methods also show the excellent matching of the predictions of the effective elastic constants and the dielectric constant of the PFRC in the useful range of fiber volume fraction. [ABSTRACT FROM AUTHOR]

Presents information on a study which obtained a closed-form solution for the optimal control of vibrations of a symmetric thin laminated plate integrated with piezoelectric layers. Information on the plate model; Results; Conclusions.

Presents a generalized finite element formulation for active vibration control of a laminated plate integrated with piezoelectric polymer layers acting as distributed sensors and actuators. Derivation of an eight-noded two-dimensional quadratic quadrilateral isoparametric element; Reduction in vibration amplitude.