A Study of A Nonlinear Viscoelastic Model for Elastomeric Bushing in Radial Mode

      

 ^†

A Study of A Nonlinear Viscoelastic Model for Elastomeric Bushing in Radial Mode

Seong Beom Lee

Key Words : Elastomeric bushing(
 ), Pipkin-Rogers model( - ), Nonlinear viscoelastic incompressible material(   )

Abstract

An elastomeric bushing is a device used in automotive suspension systems to reduce the load transmitted from the wheel to the frame of the vehicle. A bushing is an elastomeric hollow cylinder which is bonded to a solid steel shaft at its inner surface and a steel sleeve at its outer surface. The relation between the load applied to the shaft or sleeve and the relative deformation of elastomeric bushing is nonlinear and exhibits features of viscoelasticity. A load-displacement relation for elastomeric bushing is important for dynamic numerical simulations. A boundary value problem for the bushing response leads to the load-displacement relation which requires complex calculations. Therefore, by modifying the constitutive equation for a nonlinear viscoelastic incompressible material developed by Lianis, the data for the elastomeric bushing material was obtained and this data was used to derive the new load-displacement for radial response of the bushing. After the load relaxation function for the bushing is obtained from the step displacement control test, Pipkin-Rogers model was developed. Solutions were allowed for comparison between the results of Modified Lianis model and those of the proposed model. It is shown that the proposed Pipkin-Rogers model is in very good agreement with Modified Lianis model.

1.


     

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E-mail : [email protected]

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3-4, pp. 199~218.

(10) Lee, S. and Wineman, A. S., 1999, "A model for

non-linear viscoelastic axial response of an

elastomeric bushing," International Journal of Non-

Linear Mechanics, Vol. 34, No. 5, pp. 779~793.