Analysis of the dynamic characterisation and behaviour of an elevator rope

Abstract

The ropes of an elevator transmit the vibrations from the motor to the elevator car, and consequently have a great influence on comfort. Therefore, it is of major interest to analyse the dynamic behaviour of these elements, in order to know the mechanical properties of them. These ropes are composed of metallic wires and covered by a polymeric material. In the present work, the mechanical properties of the ropes employed in an elevator were identified. First, the experimental set-up for the characterisation is described. Two type of characterisations were carried out; on the one hand, the dependence of the frequency was analysed applying low preloads, and on the other hand, the effect of the preload was analysed applying the loads that the rope stands in real conditions. In both characterisations, the stiffness and the damping of the ropes were determined. According to the results obtained, an increase of the stiffness of the rope is observed as the preload is bigger and a decrease as the frequency is higher. As far as the damping is concerned, the loss factor decreases as the preload increases, as expected, while there is an increase as the frequency increases.