Stress fields and energy release rates in cross-ply laminates

A method to model the thermoelastic response of flat laminated composites using a large radius axisymmetric hollow layered cylinder model is presented. An axisymmetric concentric cylinder model and a flat laminate model, each based on Reissner's variational principle with equilibrium stress fields, are compared. The stress components and the governing equations of the axisymmetric concentric cylinder formulation for a cylinder of infinite radius are shown analytically to be equivalent to the flat laminate formulation. Numerical results for the axisymmetric free edge stress field are shown to be nearly identical to the flat laminate free edge stress field solution. Selected results for the elastic stress fields and energy release rates in composite laminates with free edge and/or internal delaminations and transverse cracking are presented. (C) 1998 Elsevier Science Ltd.