A simple equivalent plate model for dynamic bending stiffness of three-layer sandwich panels with shearing core

Multi-layered partitions have been commonly used in recent years to enhance sound comfort and noise attenuation. Sandwich composites which can exhibit high stiffness and damping with lightweight are widely employed in the transportation and building industries. This type of multi-layer is also called laminate and is often made up of three layers. One soft layer embedded between two hard skins. This kind of laminate enables to ensure a bending rigidity while increasing the dissipation by forcing the shear of the viscoelastic core. Automotive [1] and aerospace [2] industries also use sandwich structures as a passive way to reduce the structure-borne noise. Constrained layers are typically used in automobile, aircraft and railway industries to improve the damping response of the vibrating systems. In civil applications, acoustic plasterboards (with high-density core) are used to improve the sound insulation performance. Due to the increasing number of applications of multi-layer structures, there are many models available in the literature Equivalent or condensed plate models are being used in various industries to reduce the computation time in finite element modelling. Out of the available equivalent plate models, the model developed by J.L. Guyader in 1978 exhibits high agreement with Lamb wave theory but it requires some time for implementation. Therefore, in this paper, a simple model is proposed to quickly compute the dynamic equivalent parameters of a three-layer sandwich panel. Although the model is formulated from only four parameters, which could be easily computed via the asymptotic and transition behaviours of the sandwich panel, it is shown to be able to capture the equivalent dynamic response for the entire frequency range. Equivalent or condensed plate models are being used in various industries to reduce the computation time in finite element modelling. Out of the available equivalent plate models, the model developed by J.L. Guyader in 1978 exhibits high agreement with Lamb wave theory but it requires some time for implementation. Therefore, in this paper, a simple model is proposed to quickly compute the dynamic equivalent parameters of a three-layer sandwich panel. Although the model is formulated from only four parameters, which could be easily computed via the asymptotic and transition behaviours of the sandwich panel, it is shown to be able to capture the equivalent dynamic response for the entire frequency range. (c) 2021 Elsevier Ltd. All rights reserved.

Automated summary

Multi-layered partitions and sandwich composites are commonly used in various industries to enhance sound comfort, noise attenuation, and improve bending rigidity. Automotive, aerospace, and civil industries utilize these structures passively to reduce structure-borne noise, while constrained layers are applied to improve the damping response of vibrating systems.