Modelling and identification of a wire-cable vibration isolator via a cyclic loading test

Abstract

A cyclic loading test was carried out on a wire-cable vibration isolator to obtain experimentally its hysteretic behaviour in shear, roll and tension-compression respectively. In shear and roll modes, the isolator exhibits symmetric soft-hardening hysteresis loops under cyclic loading, namely the hysteresis loops display a softening stiffness in relatively small deformations and diverge to exhibiting a hardening stiffness at large deformation levels. In the tension-compression mode, the isolator exhibits asymmetric hysteresis loops, which constitute a segment of a hardening overlapping envelope in the loading curves. In recognizing the inapplicability of existing hysteretic models, two improved Bouc-Wen models are proposed within the framework of the mathematical Duhem hysteresis operator, to represent the symmetric soft-hardening hysteresis loops and the asymmetric hysteresis loops with a hardening overlapping envelope respectively.