Transverse Vibration of Viscoelastic Sandwich Structures: Finite Element Modeling and Experimental Study

Area of Science:

• Mechanical Engineering
• Materials Science
• Structural Dynamics

Background:

• Sandwich structures are vital in engineering applications requiring vibration control.
• Understanding the nonlinear vibration of elastic-viscoelastic-elastic sandwich (EVES) beams is crucial for their optimal design.
• Viscoelastic materials exhibit frequency-dependent properties that significantly influence structural behavior.

Purpose of the Study:

• To develop and validate a finite element (FE) model for analyzing the nonlinear vibration of EVES beams.
• To accurately characterize the frequency-dependent behavior of the viscoelastic core using a third-order Biot model.
• To investigate the influence of layer thickness on the predictive accuracy of the FE model for natural frequencies and damping.

Main Methods:

• Derivation of a finite element equation incorporating transverse compression deformation of the viscoelastic core.
• Utilizing a third-order seven-parameter Biot model to describe the viscoelastic material's frequency-dependent characteristics.
• Discretization of EVES beams using a 2-node, 8-degree-of-freedom (DOF) element.
• Experimental validation of the developed FE model's predictions.

Main Results:

• The FE model demonstrates high accuracy in predicting the natural frequencies of EVES beams.
• The accuracy of damping prediction is found to be dependent on the thickness of individual layers within the sandwich beam.
• Numerical and analytical investigations confirm the model's capability to capture complex vibration behaviors.

Conclusions:

• The developed FE model provides a reliable tool for analyzing nonlinear vibrations in EVES beams.
• The findings offer valuable insights into the relationship between layer thickness, natural frequency, and damping.
• This research serves as a significant reference for the design and optimization of viscoelastic sandwich structures.