Transverse Stress Effects for Laminated Composite Beams in Bending

A higher-order theory and an associated finite element formulation are developed for analysis of laminated planar beams in bending. The higher-order theory incorporates both transverse normal stress and transverse shear stress, and is developed using two approaches. The first approach is based on assuming the transverse normal strain distribution to be a cubic function through the beam thickness, while the second approach is based on assuming the transverse normal stress distribution to be a cubic function through the beam thickness. In both approaches, the transverse shear strain distribution is assumed to be a quadratic function through the beam thickness. Theoretical and finite element results for these higher-order theories are presented for isotropic, orthotropic and laminated beams in various loading conditions, and are compared with two-dimensional elasticity solutions.