This chapter focuses on investigating the dynamic transient response of viscoelastic structures. First, the influence of nonviscous modes on the vibrational response of exponentially damped systems has been studied on lumped parameter systems where the analytical solution has been derived by modal superposition and by means of Laplace transformation. Then, the analytical solution is obtained by modal superposition and compared to two numerical solutions derived for continuous systems by finite element formulations. These numerical solutions have been solved by modal superposition and by direct integration applying through a particularly built method together with the Newmark method. Finally, an experimental procedure for studying the influence that geometrical properties of viscoelastic joints have on the vibrational response of a metallic beam doubly supported on viscoelastic adhesive joints has been developed.
Part of the book: Viscoelastic and Viscoplastic Materials
This chapter focuses on the dynamic characterization of adhesive materials for vibration control proposes. First, the experimental characterization and modelization of the relaxation and complex moduli of the flexible adhesive ISR 70-03 by means of a dynamic mechanical thermal analysis technique (DMTA) are presented. Then, the interconversion path between the relaxation modulus E ( t ) and the corresponding complex modulus E * ( ω ) for linear viscoelastic solid materials is explored. In contrast to other approximate methods, in this work the fast Fourier transform (FFT) algorithm is directly applied on relaxation functions. Finally, an experimental study for the structural noise and vibration reduction in a cabin elevator by means of adhesive-bonded joints of panels is presented.
Part of the book: Adhesives