Predicting loss of bifurcation behaviour of 0/90 unsymmetric composite plates subjected to environmental loads

This paper presents an efficient Rayleigh–Ritz numerical model to predict the deformed shape and the multistable behaviour of free-standing square and rectangular 0/90 unsymmetric composite plates subjected to thermal and environmental loads. The out-of-plane displacement functions are generated through proper development of the analytical solution presented by Ashwell [34] for the nonlinear pure bending of isotropic plates; the in-plane displacement functions are formulated following a procedure similar to that employed by Galletly and Guest [32], starting from geometrical considerations about the actual deformations of the distorted structure. The resulting model is characterised by high-order displacement functions and by few unknown terms, it is appropriate to achieve sufficient accuracy, with high efficiency. The performance of the proposed approach is compared to that of some alternative models available in the literature, to FE simulations and to experimental results.