Damage Identification of Thin Textile-Reinforced Composite Plates using Vibration Based Testing Methods

摘要

Woven textiles are used as reinforcement for polymer-based composites:rnwarp and fill fiber tows are interlaced into each other to form a layer. Thernaerospace industry has been the primary driving force in the use of wovenrntextile reinforced composites. However their use in aircraft structures requires arndetailed assessment of their quality. The goal of this paper is to investigate therneffect of a fiber misorientation defect on the modal properties of glass-fiberrnwoven textile reinforced composites using experimental characterization andrnfinite element modeling. Several composite panels with controlled misalignmentrndefects were produced using VARTM process. Then, the samples wererninspected using a vibration analyzer. In addition, finite element modeling wasrnperformed to simulate the effect of fiber misorientation on the mode shapes andrnfrequency response function (FRF) of thin composite plates during vibrationrntesting. It was observed that the fiber orientation affects the dynamic behavior ofrnthe composite samples. As the fiber angle increases, the natural frequencies ofrnthe plate decrease. In addition, higher mode shapes appear to be more sensitivernto fiber misalignment. The same trend was observed in the finite elementrnmodeling results with a clear effect of the fiber orientation defect seen in FRFrnresponse and higher mode shapes.