The paper investigates the post-buckling response of web-core sandwich plates through classical continuum mechanics assumptions. The compressive loading is assumed to be in the direction of the web plates. Equivalent Single Layer (ESL) plate formulation is used with the kinematics of the First order Shear Deformation Theory (FSDT). During the initial, membrane-dominated loading stages, it is observed that the effect of finite size of the periodic microstructure is barely influences the plate responses. At the higher loads, when bending is activated, the finite size of the microstructure activates secondary shear-induced bending moments at the unit cells of the plate. A method to capture the envelope of the maximum values of these bending moments is presented. The findings are validated with the shell element models of the actual 3D-geometry. Finally, the physical limits of the classical continuum mechanics are discussed in the present context.

中文翻译：

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基于经典连续介质力学的腹板夹芯板的后屈曲：非经典公式的成功和需求

本文通过经典连续介质力学假设研究腹板夹芯板的屈曲后响应。压缩载荷假定在腹板的方向上。等效单层 (ESL) 板公式与一阶剪切变形理论 (FSDT) 的运动学一起使用。在初始的、以膜为主的加载阶段，可以观察到周期性微观结构的有限尺寸的影响几乎不影响板的响应。在更高的载荷下，当弯曲被激活时，微观结构的有限尺寸激活了板单元格处的二次剪切诱导弯矩。提出了一种捕获这些弯矩最大值的包络线的方法。研究结果通过实际 3D 几何的壳单元模型进行了验证。