Identification of material properties is one of the key issues in composite materials research. This information is the most important database for an accurate Computer-Aided Engineering (CAE) simulation and various design enhancement purposes. For example, it can be used to estimate deflections and stress state of composite structure under static or dynamic load. The mechanical properties of composite materials depend on diverse factors such as configuration of the laminates, constituent materials used, production method adopted, etc. Hence, it is generally impossible to find these properties in standard tables. Conventional testing approach tends to be time-consuming, expensive and destructive. Moreover for properties such as shear modulus, these tests often yield poor results. As an alternative, a hybrid approach which utilises experimental and numerical techniques is proposed. This approach is a rapid, inexpensive and non-destructive evaluation of the mechanical properties of composite materials which involves both Experimental Modal Analysis (EMA)
IntroductionComposite materials are composed of two or more different materials at macro-scale with each of the materials will contribute to the final properties. When the materials are combined, composites are generally more superior as compared to the individual components. Composite structures are usually constructed in multiple laminates where each layer is oriented specifically to achieve optimal strength and stiffness performance. Composites are preferred in applications due to their high strength-to-weight ratio, high-stiffness-to-weight ratio, high wear resistance, high corrosion resistance.The determination of mechanical properties is one of the important parts in composite materials research. Production method, materials used, and laminates configuration of the composites are among the contributing factors in changing the mechanical properties of composite materials. These properties are could not be found in any standard databases and tables. Conventional test procedures based on static loading are destructive, time and cost consuming. In addition, these tests often produce poor results especially in determining properties such as shear modulus. This has encouraged the development of specific methods to improve the accuracy in the identification method. Modal parameter such as mode shape or the combination of both natural frequencies and mode shapes are rarely used in elastic constants determination.In this paper, a non-destructive evaluation of the mechanical properties of composite materials which involves EMA and Finite Element (FE) model updating method is proposed. This approach utilises
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