抄録
This paper describes vibration analysis using finite element method for elastic block connected by nonlinear concentrated springs with nonlinear hysterisis. The restoring force of the spring has cubic nonlinearity and nonlinear hysterisis damping. Finite element for the nonlinear spring having complex coefficients is expressed and is connected to the elastic block modeled by linear solid finite elements in consideration of complex modulus of elasticity. Further, the discredited 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.