الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
This thesis is devoted to study the bending analysis of hygro-thermal effect on a composite plate resting on elastic foundations. The plates are assumed to be cross-ply laminated or EG and FG materials. Some of the basic concepts of the theory of elasticity for composite materials are presented. There are five problems in the present thesis. New investigations for simply-supported composite structures are discussed in the first and five problems. These structures are assumed to be made of n layers oriented at angles θ1, θ2,...,θn. The material of each layer is assumed to posses one plane of elastic symmetry parallel to the x-y plane. The bending response of an orthotropic rectangular plate resting on two-parameter elastic foundations under thermo-mechanical loadings is investigated as a first problem. Analytical solutions for deflection and stresses are presented by using a unified shear deformation plate theory. The influences of material anisotropy, aspect ratio, side-to-thickness ratio, thermal expansion coefficients ratio and stacking sequence on the thermally induced response are studied. New investigations for a simply-supported composite structure are discussed in the second, third and four problems. These structures are EG or FG plates, meaning that Lamé’s coefficients of the present plate vary exponentially in a given fixed direction or Young’s modulus E, and thermal α and moisture expansion β coefficients may be assumed to follow the power law. The second problem deals with the solution of EG thick plates resting on Winkler-Pasternak elastic foundations based on a new trigonometric shear deformation theory. This theory includes the effect of both shear and normal deformations and it is simplified by enforcing traction-free boundary conditions at the plate faces. In the third problem, the trigonometric shear deformation plate theory is used to study the thermomechanical bending analysis of EG thick rectangular plates resting on Pasternak’s elastic foundations. The plate is subjected to sinusoidally/uniformly distributed load and a temperature field. A comparison with the result available in the literature is given. In the forth problem, the effects of temperature and moisture on the response of functionally graded plates resting on elastic foundations. The effects of transverse shear strains as well as the transverse normal strain are taken into account. The number of unknown functions involved in the present theory is only four as against six or more in case of other shear and normal deformations theories. The last problem is concerned with the influence of temperature and moisture on the bending behavior of laminated composite plates resting on elastic foundations using a refined plate theory. The material properties of the composite are affected by the variation of temperature and moisture