This paper investigates stability and free vibration behaviours of bi-directional functionally graded material (BDFGM) curved sandwich beams. Simultaneous variation of material compositions along tangential and radial direction is considered. A three-node curved isoparametric beam element based on a 4-parameter global–local shear deformation theory is employed. The obtained results are verified with those from literature. Various parameters such as aspect ratio, deepness ratio, gradient indexes, boundary conditions are taken into account. Several results of BDFG curved beams are provided for benchmark purpose.

中文翻译：

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双向FG弯曲夹层梁稳定性和振动分析的有限元模型

本文研究了双向功能梯度材料（BDFGM）弯曲夹层梁的稳定性和自由振动行为。考虑材料成分沿切向和径向的同时变化。采用基于四参数全局-局部剪切变形理论的三节点弯曲等参梁单元。所得结果与文献结果进行了验证。考虑了纵横比、深度比、梯度指数、边界条件等各种参数。提供了 BDFG 曲梁的几个结果用于基准目的。