Free vibration analysis of fiber reinforced composite beams using higher order theories and finite element modelling

Three higher order refined displacement models are proposed for the free vibration analysis of sandwich and composite beam fabrications. These theories model the warping of the cross-section by taking the cubic variation of axial strain and they eliminate the need for a shear correction coefficient by assuming a quadratic shear strain variation across the depth of the cross-section. Numerical experiments for various lamination schemes, boundary conditions and aspect ratios are carried out to compare these models with the first order shear deformation theory, earlier investigations and also among themselves to ascertain the most efficient one. Numerical results for deep sandwich and composite beams are also presented for future references. (C) 1996 Academic Press Limited