Experimental verification on simplified estimation method for envelope curve of wrinkled membrane surface distortions
Experimental verification on simplified estimation method for envelope curve of wrinkled membrane surface distortions
复制标题
DOI：
10.1016/j.tws.2017.10.049
复制
发表时间：
2018
影响因子：
6.4
通讯作者：
T. Iwasa
中科院分区：
文献类型：
--
作者：
T. Iwasa
对作者最近提出的一种估算皱膜表面变形包络曲线的简化方法的有效性进行了实验评估。该方程使用关于皱纹的三个物理量：皱纹线的长度、皱纹区的主要主应变和皱纹线垂直方向上出现的面内收缩应变来表示。由于这三个物理量都归因于二维问题，因此该公式可以简单地估计褶皱幅度，而不需要进行繁琐的分叉分析。采用张力场理论中的褶皱应变代替公式中的面内收缩应变，利用张力场理论进行褶皱分析，提出了一种计算成本较低的估算起皱薄膜包络曲线的简化方法。利用直接线性变换法和激光位移传感器对两种薄膜模型在面内剪切和角部拉伸载荷作用下出现的起皱现象进行了实验测量。然后利用张力场理论对实验模型进行了有限元分析，并用该方法估算了起皱薄膜的包络曲线。无论皱纹的形成过程如何，估计的包络曲线都适当地捕捉到了出现在膜表面上的实际皱纹幅度。结果表明，所提出的估计方法是有效的。本文提供了一种以较低的计算代价预测起皱膜表面变形量的有效方法，并将有助于未来含膜薄纱空间结构的发展。
The effectiveness of a simplified method for estimating an envelope curve of wrinkled-membrane-surface distortion, which was recently proposed by the author, was experimentally assessed. The equation is formulated using three physical quantities regarding wrinkles: the length of the wrinkle line, the major principal strain in wrinkled regions, and the in-plane shrinkage strain appearing in the orthogonal direction of the wrinkle line. Since these three physical quantities are attributed to two-dimensional problems, the formula makes it possible to simply estimate wrinkle amplitude without a cumbersome bifurcation analysis. Applying a wrinkle strain in tension-field theory instead of the in-plane shrinkage strain in the formula, a simplified method to estimate an envelope curve of a wrinkled membrane with a low computational cost was developed using the wrinkling analysis with tension-field theory. Wrinkling phenomena appearing on two membrane models subjected to an in-plane shear and a corner-tension load were experimentally measured by photogrammetry using the direct linear-transformation method and a laser-displacement sensor. The experiment model was then subjected to a finite element analysis using tension-field theory, and an envelope curve of the wrinkled membrane was estimated using the method. The estimated envelope curves appropriately captured the actual wrinkle amplitude appearing on the membrane surface regardless of the formation process of wrinkles. From the result, the validity of the proposed estimation method was confirmed. This paper offers an effective method to predict the magnitude of the wrinkled-membrane-surface distortion with a low computational cost, and will assist the development of future gossamer space structures incorporating membranes.