Boundary resonant modulation of an inextensible cantilever beam coupled with the moving foundation
摘要
In this paper, we develop an inextensible cantilever beam model coupled with moving foundation to study two-way dynamic coupling behaviors with the consideration of nonlinear inertia and stiffness. Based on the concept of boundary resonant modulation, moving foundation-induced vibration of the beam is asymptotically perturbed into its slow dynamics using direct multi-scale method. Boundary resonant modulation term and effective nonlinearity coefficients characterizing the nonlinear inertia and stiffness are cleared out. Parametric influence of key factors on coupling dynamics, including inertia effect of top mass, mass ratio of top mass to total mass of beam, and mass ratio of foundation to total mass of beam, are discussed. Results show the hardening spring in first mode frequency response dominating by nonlinear stiffness, and a transition to softening spring with the consideration of inertia effect of top mass; the motion of moving foundation can suppress vibration of cantilever beam in the primary resonance domain to some extent.