层间过渡约束阻尼梁有限元建模与振动-阻尼特性分析

三层约束阻尼结构常被用于工程结构的减振降噪设计中,为了增加其抗振性能,可在黏弹层和基层中间加入一层"过渡层",从而构成一种新的层间过渡约束阻尼结构。基于一阶剪切变形理论和哈密顿原理建立有限元模型,对该结构进行相应的振动和阻尼特性分析。为验证该模型正确性,与解析解进行对比,二者计算结果吻合良好。以悬臂阻尼梁为例,与传统的约束阻尼梁进行对比,计算结果表明增加"过渡层"可以增大结构的损耗因子,进而提高减振耗能效果。同时还讨论了过渡层的材料如何选择以及其参数对系统的固有频率和损耗因子的影响,为进一步的优化工作及实际工程应用提供了一定的参考。

FINITE ELEMENT MODELING AND VIBRATION-DAMPING CHARACTERISTICS OF A CONSTRAINED DAMPING BEAM WITH TRANSITION LAYER

The three-layer constrained damping structure is often used in the design of vibration and noise reduction for engineering structures.A "transition layer" can be added in the middle of the viscoelastic layer and the base layer to form a new kind of constrained damping structure with transition layer in order to increase its anti-vibration performance.Based on the first-order shear deformation theory and Hamilton principle,the finite element model is established,and the corresponding vibration and damping characteristics are analyzed.In order to verify the correctness of the model,the two results are in good agreement compared with the analytical solution.Taking the cantilever damping beam as an example,compared with the traditional constrained damping beam,the calculation results show that adding the "transition layer" can improve the loss factor of the structure and energy consumption.At the same time,the material of the transition layer selection and influence of its parameters on the natural frequency and the loss factor of the system are discussed,which lay a good foundation for further optimization and engineering practice.