Dynamics of delaminated smart composite cross-ply beams

A refined higher order theory-based finite element model is presented for modeling the dynamic response of delaminated smart composite cross-ply beams. The refined displacement field accurately accounts for transverse shear deformations through the thickness, and all traction-free boundary conditions are satisfied at all free surfaces including delamination interfaces. The developed theory provides an accurate, computationally efficient analysis tool for the study of smart composite cross-ply beams with piezoelectric sensing and actuation in the presence of delamination. The theory is implemented using the finite element method to allow the incorporation of practical geometries, boundary conditions and the presence of discrete piezoelectric transducers. A new formulation is presented to include nonlinear induced strain effects. Vibration control is accomplished by piezoelectric layers incorporated in the composite beam. The resulting finite element model is shown to agree well with published experimental data, and the results show significant improvements compared to existing analytical solutions. Numerical results presented in the paper indicate changes in natural frequencies, mode shapes and dynamic responses due to delaminations.