Vibrations of unsymmetrically laminated plates analyzed by using a higher order theory with a C° finite element formulation
Recently developed shear deformation theory is used to analyze vibrations of laminated composite and sandwich plates in conjunction with a C° isoparametric finite element formulation. The present theory is based on a higher order displacement model and the three-dimensional Hooke's laws for plate material, giving rise to a more realistic representation of the cross-sectional deformation. The theory does not require the usual shear correction coefficients generally associated with Reissner-Mindlin theories. A special mass lumping procedure is used in the dynamic equilibrium equations. The numerical examples presented are compared with 3-D elasticity/analytical and Mindlin's plate solutions, and it is demonstrated that the present model predicts the frequencies more accurately when compared with the first order shear deformation theories and classical plate theories.