Buckling and postbuckling nonlinear analysis of imperfect FGM plates reinforced by FGM stiffeners with temperature-dependent properties based on TSDT

Using Reddy’s third-order shear deformation plate theory (TSDT) with von Kármán geometrical nonlinearity, this work presents an analytical solution on the buckling and postbuckling behaviors of eccentrically stiffened functionally graded material (ES-FGM) plates on elastic foundations subjected to in-plane compressive loads or thermal loads or thermo-mechanical loads. Plates are reinforced by closely spaced FGM stiffeners. The material properties of the plate and stiffeners are assumed to be temperature-dependent. Theoretical formulations based on the smeared stiffeners technique and TSDT are derived. The expressions of thermal parameters are found in the analytical form. Applying Galerkin method, the expressions to determine the critical buckling load and analyze the postbuckling mechanical and thermal load–deflection curves are obtained. Two iterative algorithms are presented for the case of temperature-dependent plate material properties. The effects of thermal element, FGM stiffeners, geometrical and material parameters, initial imperfection, and foundation are considered and discussed. By comparing the present results with those in references, the accuracy of the present study is affirmed.