Bending analysis of FGM plates under hygro-thermo-mechanical loading using a four variable refined plate theory

The bending response of functionally graded material (FGM) plate resting on elastic foundation and subjected to hygro-thermo-mechanical loading is studied. Using a four variable refined plate theory, both a quadratic variation of the transverse shear strains across the thickness and the zero traction boundary conditions on the top and bottom surfaces of the plate are satisfied without using shear correction factors. The number of independent unknowns of present theory is four, as against five in other shear deformation theories. The elastic coefficients, thermal coefficient and moisture expansion coefficient of the plate are assumed to be graded in the thickness direction. The elastic foundation is modelled as two-parameter Pasternak foundation. Numerical results are presented to verify the accuracy of present theory and the influences played by many parameters are investigated. The study is relevant to the simulation of rocket launch pad structures subjected to intense thermal loading.