In this research, it has been tried to study the mechanical behavior of a micro annular circular sheet made of microcrystalline cellulose material. A new combination between the modified higher-order shear deformation, also, quasi-three-dimensional displacement fields and the modified couple stress theory has been presented for simulating the mentioned micro-sheet under the transverse loading. Consequently, two types of two and three-dimensional equations in micro-size have been obtained. By solving the obtained governing equations with semi-analytical polynomial method, deflection results have been depicted in form of several diagrams. Due to the use of modified couple stress theory, there is a micro-scale parameter in the analysis that requires laboratory experiments for determining its specific values. Due to this purpose, a micro-cellulose sheet has been tested to determine its deformations under the transverse loading, in consequence, the micro-length scale parameter has been calculated by comparison between the theoretical and test results. It is demonstrated that the size of the analyzed sheet (here the amount of its radius) has the most impact on the value of micro-length scale parameter. This research can be very useful for researchers who study the micro-scale parameter in couple stress theory as well as the interesting properties of structures made of microcrystalline cellulose.

在这项研究中，已尝试研究由微晶纤维素材料制成的微环形圆片的力学行为。提出了改进的高阶剪切变形、准三维位移场和改进的耦合应力理论之间的新组合，用于模拟横向载荷下的上述微薄板。因此，得到了两种类型的二维和三维微观尺寸方程。用半解析多项式法求解得到的控制方程，将偏转结果用多张图的形式表示出来。由于使用了修正偶应力理论，分析中有一个微尺度参数，需要实验室实验来确定其具体值。由于这个目的，测试了微纤维素片材在横向载荷下的变形，从而通过理论和测试结果的比较计算了微长度尺度​​参数。结果表明，分析片材的尺寸（此处为其半径量）对微长度尺度​​参数值的影响最大。这项研究对于研究偶应力理论中的微观参数以及由微晶纤维素制成的结构的有趣特性的研究人员非常有用。结果表明，分析片材的尺寸（此处为其半径量）对微长度尺度​​参数值的影响最大。这项研究对于研究偶应力理论中的微观参数以及由微晶纤维素制成的结构的有趣特性的研究人员非常有用。结果表明，分析片材的尺寸（此处为其半径量）对微长度尺度​​参数值的影响最大。这项研究对于研究偶应力理论中的微观参数以及由微晶纤维素制成的结构的有趣特性的研究人员非常有用。