In this article, the nonlinear thermomechanical buckling behaviors of sandwich functionally graded plates subjected to an axial compression and external pressure are analytically analyzed resting on nonlinear elastic foundation. Assuming that the plates are reinforced by oblique stiffeners and rested on nonlinear elastic foundation. The formulations are established using the higher-order shear deformation theory taking into account the geometrical nonlinearity of von Kármán. The Lekhnitskii’s smeared stiffener technique is developed for shear deformable oblique stiffener system using the coordinate transformation technique with both mechanical and thermal terms. The Galerkin method is utilized to obtain the nonlinear algebraically equation system, then, solve it to determine the explicit expressions of critical buckling loads and postbuckling load–deflection curves. Numerical results show the effects of temperature, nonlinear elastic foundation, stiffeners, and material and geometrical properties on nonlinear behaviors of plates.

在本文中，基于非线性弹性基础，分析了夹层功能梯度板在轴向压缩和外部压力作用下的非线性热机械屈曲行为。假设板由斜加劲肋加固，并置于非线性弹性基础上。考虑到vonKármán的几何非线性，使用高阶剪切变形理论建立公式。Lekhnitskii的涂抹加劲肋技术是针对剪切变形的斜加劲肋系统而开发的，它使用了机械和热力方面的坐标变换技术。利用Galerkin方法获得非线性代数方程组，然后，通过求解确定临界屈曲载荷和屈曲后载荷-挠度曲线的明确表达式。数值结果表明温度，非线性弹性基础，加强筋以及材料和几何特性对板的非线性行为的影响。