Thai Duc-Kien, Tu Tran Minh, Hoa Le Kha, Hung Dang Xuan, Linh Nguyen Ngọc
Department of Civil and Environmental Engineering, Sejong University, 98 Gunja-dong, Gwangjin-gu, Seoul 143-747, Korea.
Faculty of Industrial and Civil Engineering, University of Civil Engineering, Hanoi 100000, Vietnam.
Materials (Basel). 2018 Nov 6;11(11):2200. doi: 10.3390/ma11112200.
This paper analyzes the nonlinear buckling and post-buckling characteristics of the porous eccentrically stiffened functionally graded sandwich truncated conical shells resting on the Pasternak elastic foundation subjected to axial compressive loads. The core layer is made of a porous material (metal foam) characterized by a porosity coefficient which influences the physical properties of the shells in the form of a harmonic function in the shell's thickness direction. The physical properties of the functionally graded (FG) coatings and stiffeners depend on the volume fractions of the constituents which play the role of the exponent in the exponential function of the thickness direction coordinate axis. The classical shell theory and the smeared stiffeners technique are applied to derive the governing equations taking the von Kármán geometrical nonlinearity into account. Based on the displacement approach, the explicit expressions of the critical buckling load and the post-buckling load-deflection curves for the sandwich truncated conical shells with simply supported edge conditions are obtained by applying the Galerkin method. The effects of material properties, core layer thickness, number of stiffeners, dimensional parameters, semi vertex angle and elastic foundation on buckling and post-buckling behaviors of the shell are investigated. The obtained results are validated by comparing with those in the literature.
本文分析了基于Pasternak弹性地基上的多孔偏心加劲功能梯度夹层截顶圆锥壳在轴向压缩载荷作用下的非线性屈曲和后屈曲特性。芯层由多孔材料（金属泡沫）制成，其孔隙率系数以壳厚度方向的调和函数形式影响壳的物理性能。功能梯度（FG）涂层和加劲肋的物理性能取决于成分的体积分数，这些成分在厚度方向坐标轴的指数函数中起指数的作用。应用经典壳理论和加劲肋涂抹技术，考虑von Kármán几何非线性，推导控制方程。基于位移法，通过Galerkin方法得到了简支边界条件下夹层截顶圆锥壳的临界屈曲载荷和后屈曲载荷-挠度曲线的显式表达式。研究了材料性能、芯层厚度、加劲肋数量、尺寸参数、半顶角和弹性地基对壳屈曲和后屈曲行为的影响。通过与文献结果比较，验证了所得结果的正确性。
