Abstract
This paper describes vibration analysis using finite element method for box consisting of elastic plates and damping layers connected by nonlinear concentrated springs. The restoring force of the springs have cubic nonlinearity and linear hysteresis damping. Finite element for the nonlinear springs are expressed and are connected to the elastic plate modeled by linear solid finite elements in consideration of complex modulus of elasticity. Further, the discretized equations in physical coordinate are transformed into the nonlinear ordinary coupled equations using normal coordinate corresponding to linear natural modes. This transformation yields computation efficiency. We evaluate the influences of the damping layer on the linear/nonlinear impact responses. Moreover, we also investigate the influences of stiffness for the bottom plate in the box on the impact responses.
