Maxwell–Voigt and Maxwell Ladder Models for Multi Degree of Freedom Elastomeric Isolation Systems

Abstract

This paper presents a model for an elastomeric isolation system consisting of a three degreeoffreedom (DOF) rigid body assembled to a frame through multiple isolators. Each elastomeric isolator is either represented by a Maxwell–Voigt (MV) model consisting of two Maxwell elements or by a Maxwell ladder (ML) model consisting of three Maxwell elements. The MV models and the ML models are characterized by using experimental data that are collected at multiple excitation frequencies. The characterized models are evaluated and used to simulate the performance of the isolation system. The models developed in this paper are capable of representing frequencydependent behavior that is exhibited by elastomeric isolators and the overall isolation system. Furthermore, the proposed model is capable of directly associating the behavior of the isolation system with physical and geometrical properties of each isolator. The proposed model is expected to be a useful tool for the analysis and design optimization of elastomeric isolation systems. Most of the isolation systems in practical applications exhibit multiple DOF, this model will be particularly useful in such applications since it does not constrain motion to translation only. This is a shortcoming of the models in the current literature that the proposed model attempts to overcome.