Structural Characteristics of Membranes & Shells and Applications to Non-Destructive Inspection using 3D Measurement and Holographic Interferometry

本文利用三维测量、全息干涉仪和电子散斑干涉仪(ESPI)研究了壳膜结构的结构特征及其在无损检测中的应用。主要研究成果如下：(A)对FRP复合材料层合板的振动特性进行了理论分析和实验研究。利用全息干涉仪获得了系统的共振振动模式。振动频率和振型分析结果与实验结果吻合较好。缺陷玻璃钢板材的无损检测是今后的研究方向。(2)在缺陷铝板的拉伸试验中，应用了电子散斑干涉技术。菌株的本地化和发展已经能够可视化。应用电子散斑干涉技术观察了矩形拉伸…拉伸试验中起皱的产生过程更多的膜结构。实验结果表明，起皱发生在载荷最小主应变的拐点。在此基础上，利用三维光学测量装置对薄膜的皱纹进行了三维测量。未来的主题是开发高精度的测量设备并通过理论分析进行模拟。(D)在使用暴露于丙酮蒸发的PMMA样品进行的双轴压缩试验中，宏观剪切断层之前出现了一系列微小的裂缝或银纹。基于断裂力学的数值分析发现，存在着一种特殊的排列方式，在这种排列中，构成裂缝的每一条裂缝都可以张开，即使在双向压缩下也表现出I型变形。(E)利用电子散斑干涉技术观察了混凝土硬化过程与钢筋混凝土梁弯曲和剪切裂缝的产生和发展之间的收缩应变，并实现了可视化。未来的主题是通过有限元、SPH和DEM LESS等理论分析进行模拟

This study focused on structural characteristics of shell & membrane structures using three dimensional measurement, holographic interferometer and electronic speckle pattern interferometer(ESPI), and its applications to non-destructive inspection. The obtained results can be summarized as follows.(a)The vibration characteristics of FRP laminated composite plates have been analytically and experimentally investigated. The resonance vibration modes are obtained by using holographic interferometer. The vibration frequencies and modes between analytical and experimental results were good agreement. Non-destructive inspection of defective FRP plate is future theme.(b)In tensile test of defective aluminum plates, ESPI has been applied. Localization and development of strain have been able to visualize. The future theme is to simulate by FE analysis and fracture mechanics technique.(c)ESPI has been applied to observe a wrinkling generation process of tensile test of the rectangular tensioned … More membrane structures. It is found from the experimental results that wrinkling occurs at an inflection point of the load-minimum principal strain. Furthermore, using 3D-optic measuring device, the wrinkle of membrane has been measured three-dimensionally. The future theme is to develop high accuracy measurement equipment and to simulate by theoretical analysis.(d)In a biaxial compression test using PMMA samples exposed acetone evaporation, a macroscopic shear-faulting was preceded by an appearance of array of minute cracks or crazes. It was found from the fracture mechanics based numerical analysis that there exist a special arrangement in which each of crack constitutes the array can open exhibiting mode-I deformation even under biaxial compression.(e)ESPI has been applied to observe a shrinkage strain between concrete hardening process and the generation and development of bending and shearing cracking in RC beams, and it was possible to visualize. The future theme is to simulate by theoretical analysis such as FE,SPH,and DEM Less