STRAIN ENERGY AND DAMPING ANALYSIS OF COMPOSITE LAMINATES WITH TWO INTERLEAVED VISCOELASTIC LAYERS

The linear bending of symmetric laminates with two interleaved viscoelastic damping layers is analyzed. The viscoelastic layer is treated as the isotropic material. The strain energy stored in in-plane as well as in transverse shear is considered. The Ritz method is employed to investigate the strain energy of individual stress components. Taking a square plate with four edges clamped as an example, the individual stress components and their strain energy for both composite materials and the viscoelastic layers are calculated, and the loss factor of the mixed structures is discussed. The results show that the total energy is mainly contributed by the in-plane strain energy in the panel layers of composites and the shear strain energy in xz and yz directions in the viscoelastic damping layers. The strain energy in the middle layer of composites is negligible.