Yang W, Fung T C, Chian K S, Chong C K
School of Civil and Environmental Engineering, Nanyang Technological University, Singapore.
J Biomech. 2007;40(3):481-90. doi: 10.1016/j.jbiomech.2006.02.020. Epub 2006 May 4.
The mucosal folding is a phenomenon observed for some biological tissues, including the pulmonary airway and gastrointestinal tract. In order to understand the mechanism of the formation of mucosal folding, a thick-walled two-layered cylindrical mathematical model was developed to investigate the buckling behavior under the external pressure and circular outer boundary condition. With the finite element method, the validity and accuracy of the proposed model was verified. The results showed that the fold number was in the range of 4-6, which was agreed with the experimental observation for the mucosal folding of a porcine esophagus. The fold number was found to decrease with the increase in the ratio of the inner to outer material stiffness. The increase in the thickness of inner layer also caused a slight declination of the fold number. Since the effects of both the material and geometrical nonlinearities have been accounted for, this model is more general to be used for the prediction of the buckling behavior of the layered structure with a wide range of thickness ratios and/or stiffness ratios.
黏膜褶皱是在包括肺气道和胃肠道在内的一些生物组织中观察到的一种现象。为了理解黏膜褶皱的形成机制，建立了一个厚壁双层圆柱数学模型，以研究在外压和圆形外边界条件下的屈曲行为。采用有限元方法，验证了所提模型的有效性和准确性。结果表明，褶皱数在4 - 6范围内，这与猪食管黏膜褶皱的实验观察结果一致。发现褶皱数随内外材料刚度比的增加而减少。内层厚度的增加也导致褶皱数略有下降。由于考虑了材料和几何非线性的影响，该模型更具通用性，可用于预测具有广泛厚度比和/或刚度比的层状结构的屈曲行为。
