频率相关自由阻尼层复合材料加筋板动力分析

采用子空间迭代法和精细积分对敷设粘弹性阻尼层的含损伤复合材料加筋板结构进行了频率和动力响应分析。分析中对层合板和层合梁采用了Adams应变能法与Raleigh阻尼模型相结合的阻尼矩阵构造方法;对表面粘弹性阻尼材料则考虑了材料性质和耗散系数对激振频率与温度的依赖性,建立了频率相关粘弹性材料阻尼矩阵的计算方法。通过有限元分析,分别研究了敷设自由阻尼层无损伤和含分层损伤复合材料加筋板的自振频率和模态特征,并根据幅频曲线讨论了阻尼材料模量、耗散系数和阻尼层厚度等因素对结构响应的影响,提出的计算方法对通过合理选择阻尼层材料与几何参数来有效地控制加筋板结构的振动特性,具有一定的参考价值。

DYNAMIC CHARACTERISTICS OF COMPOSITE REINFORCED LAMINATES ATTACHED WITH FREQUENCY-DEPENDANT DAMPING LAYERS

An efficient natural frequency and dynamic responses analysis for damaged composite reinforced laminated structures attached with viscoelastic damping layer is presented by sub-space iterative method and precise time-integration method. The damping matrix of the laminates and the stiffeners are constructed combining Adams strain energy method and Rayleigh damping model. The dependence on mechanical properties, the loss factors on the frequency, and the temperature of the unconstrained viscoelastic-damping layer are taken into account. The natural frequencies and mode shapes of composite reinforced laminates with unconstrained damping layer with/without considering delaminations are investigated in the analysis. The effects of elastic ratio, the loss factor and the thickness of unconstrained damping layer on the response of composite stiffened laminates with damping layer are discussed. The method presented is quite useful for controlling the resonance of reinforced laminated structures effectively, and selecting the materials and geometric parameter of the damping layer rationally.