State-space method for dynamic responses of double beams with general viscoelastic interlayer

Due to their effective engineering applications, double-beam systems have intensively been studied in recent decades. The interlayer between beams in the system plays a key role in the structural vibration and energy dissipation. However, existing research efforts only observe the pure elastic interlayer or simplest viscoelastic interlayer such as Kelvin-model interlayer. In this paper, a general viscoelastic interlayer that can consider more complex stiffness and damping effects is investigated. A novel state-space approach with the proposed mode-shape constant is presented to determine the transverse vibration of the double-beams. The given integrals of mode shapes can effectively decouple the governing equations, making it possible to analyze the complex viscoelastic interlayer. Numerical examples demonstrate that the proposed method is accurate and reliable. The viscoelastic interlayer affects the natural frequencies of asynchronous vibration mode more apparently than those of synchronous vibration mode. The damping coefficients of the viscoelastic interlayer have a significant effect on the damping characteristic of the double-beam systems while reducing the dynamic responses of the beams in the forced vibration. The proposed method can be useful to simulate the dynamic responses of double-beam systems with various viscoelastic interlayers in engineering practices and applications.