The influence of a coupling nonlinear spring-mass system on dynamic responses of a generally restrained double-beam structure

This is the authors' abstract. We don't add key points for this paper.

On various engineering occasions, complex structures are typically simplified as several-beam structures jointed by coupling devices. Coupling devices can be divided into rigid and elastic coupling cases. The elastic coupling device is regarded as a spring-mass system. When the coupling device is high-elastic, the equivalent stiffness of the elastic coupling device exhibits nonlinear characteristics. The existing studies related to double-beam structures are mainly limited to the linear case. There are few studies investigating the dynamic responses of the double-beam structure jointed by a nonlinear spring-mass system. Considering the engineering practice, this study establishes the vibration analysis model of a generally restrained double-beam structure coupled with a nonlinear spring-mass system. The governing equations of the double-beam structure and the coupling nonlinear spring-mass system are derived through the generalized Hamiltonian principle and the variational procedure. The Galerkin truncation method (GTM) is employed to predict the dynamic response of such a double-beam structure. On this basis, the influence of the coupling nonlinear spring-mass system on dynamic responses of the double-beam structure is investigated. It can be concluded that the GTM has good stability and correctness for predicting dynamic responses of the double-beam structure with a coupling nonlinear spring-mass system. Dynamic responses of such a double-beam structure are sensitive to their initial calculation values. Suitable coupling nonlinear stiffness beneficially influences vibration suppression and significantly changes the kinetic energy transfer characteristics of the double-beam structure. Additionally, single-frequency responses can be transferred into multi-frequency responses under a suitable coupling nonlinear stiffness.