Research Of Vibration Analysis Method For Composite Components With Laminated Structure

Fiber-reinforced composite materials are more widely used in high-tech field of aeronautics andastronautics, wind power etc. In addition to advantages of high specific strength and specific stiffness,vibration resistance and design versatility etc, it also has excellent damping characteristics. Therefore,it is beneficial for controlling vibration and improving the structural ability to withstand cyclic andimpact loads. In recent years, the research on the vibration characteristics of laminated composites hasreceived extensive attention.Three areaes of research has been done for composite laminates: First, the mechanism andforecasting methods of composite material damping were discussed, then the damping forecastingmodel of composite laminates has been established at the station of different overlay methods,different thickness, different materials, etc. Meanwhile, a software program related to the dampingprediction has been developed to simulate some different composite laminates. Second, the finiteelement dynamic analysis models of no-damaged, hole-damaged and delamination-damagedcomposite laminates has been built., then the modes of laminates has been calculated under theconditions of free and one end fixed. On this basis, the vibration analysis of laminates has been madefor three parts: no-damaged laminates with different overlay methods and geometrical parameters,hole-damaged laminates with different hole locations and sizes, delamination–damaged laminateswith different stiffness, depth and size. Third, the modal experiment has been done for differentlaminates. The results show that the models of damping forecasting and finite element simulation arevalid.A certain reference value has been gived on vibration analysis of composite structures. Equivalentdamping coefficient in the constitutive equations can be easily derived through the dampingpredictive models, then the equivalent damping matrix of laminates with any layers and angles can beconveniently got. The models of finite element simulation provide a powerful tool for fast andaccurately evaluating the dynamic mechanical properties of composite materials, so they have a veryimportant engineering significance.