On the modelling of non-linear elastomeric vibration isolators

Vibration isolators consisting of polymeric materials exhibit non-linearity in their stiffness and damping characteristics. Two different approaches t owards modelling these non-linear characteristics are discussed. In one app roach, experimentally obtained hysteresis loops are modelled through a suit able constitutive equation. In the other, experimentally obtained harmonic, displacement transmissibility plots are modelled by expressing the restori ng and damping forces through lower order polynomials of deformation and ra te of deformation, respectively. In both cases, it is observed that the dyn amic stiffness, which is more than the static stiffness, exhibits a small s oftening type non-linearity. The non-linearity in the damping characteristi c is seen to be more pronounced than that in the stiffness. (C) 1999 Academ ic Press.