Three-dimensional exact hygro-thermo-elastic solutions for multilayered plates: Composite laminates, fibre metal laminates and sandwich plates

Abstract

Three-dimensional (3D) exact hygrothermal elasticity solutions are developed to study the behaviour of simply supported rectangular multilayered composite plates, considering any combination of orthotropic and/or isotropic layers, under hygro-thermo-mechanical loadings. In agreement with the 3D exact elasticity solutions derived by Pagano in the early 1970s, the form of the through-thickness exact solutions of any given layer depends, in fact, on whether the layer material is isotropic or (at most) orthotropic. The 3D exact thermoelastic solutions found, already available, consider either only isotropic layers or only (at most) orthotropic composite layers. This work aims to be all-inclusive, in addition to a further development by considering hygrothermal elasticity. The results here presented consider composite laminates, fibre metal laminates and sandwich plates with different side-to-thickness ratios under a series of hygro-thermo-mechanical loadings. A transverse mechanical load and/or thermal load and/or hygroscopic load are imposed on the multilayered plate top and bottom surfaces to study the effects of hygrothermal environments in the multilayered plate behaviour. These effects are demonstrated by the through-thickness distributions of displacements, stresses, temperature and weight percent moisture content for the selected multilayered plates under different hygro-thermo-mechanical loadings, which may serve as 3D benchmark exact solutions.