获取黏弹性材料频率依赖性对复合结构振动特性的影响，对于黏弹性复合结构建模及阻尼减振具有重要的意义。在合理引入黏弹性材料力学特性参数的基础上，创建了处于基础激励状态并且考虑频率依赖性的黏弹性复合结构动力学分析模型，并获得了复合结构固有特性和振动响应的求解公式。以贴敷黏弹性阻尼材料的悬臂钛板为例，用试验对所研发的模型进行了验证。最后，基于所创建的模型，分析了悬臂板贴敷两种不同的阻尼材料时，黏弹性材料的频率依赖性对复合结构振动特性的影响。具体可描述为：求解复合结构固有频率和非共振响应时可忽略黏弹性材料的频率依赖性，而求解模态损耗因子和共振振动响应时，需要引入黏弹性材料的频率依赖特性；假如不考虑频率依赖性，取黏弹性材料参数所考虑频率范围的平均值获得的结算结果与考虑频率依赖性时的结果更为接近。
It is of great importance that obtaining the effects of frequency dependent characteristic on the vibration of viscoelastic composite structure during the dynamic modeling and vibration reduction design. On the basis of introducing the mechanical parameters appropriately, the dynamic model of viscoelastic composite structure under base excitation is established considering the frequency dependent characteristic and the formulas of solving the natural characteristics and vibration response are obtained. Furthermore, the thin cantilever titanium plate attached the viscoelastic damping material is chosen and an experiment is performed to verify the rationality of the developed method. Finally, using the model, the effects of frequency dependent characteristic on the vibration of viscoelastic composite plate are analyzed for the thin plate attached two kinds of different viscoelastic materials. They can be presented as follows. When calculating the natural frequencies and the non-resonances, the frequency dependent characteristic of viscoelastic material can be neglected. While solving the modal loss factors and the resonance responses of composite structure, the frequency dependent characteristic of viscoelastic material needs to be considered. If the frequency dependent characteristic is not included in the model, the results corresponding to the average values of viscoelastic parameters in the considered frequency range are more closed to the results obtained by considering the frequency dependent characteristic.
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