Free Vibration of Elevator Rope with Vibration Suppressors (When Vibration Suppressors are arranged at Equal Intervals)

Abstract

When an elevator rope for a high-rise building is forcibly excited by the displacements of the building induced by wind forces and/or by long-period ground motion. In previous paper, when elevator cage is stationary, a new practical method for reducing the rope vibration by using vibration suppressors is proposed for relaxing the restricted elevator operation. The advantage of using the vibration suppressors for reducing the rope lateral vibration is demonstrated through numerical calculation. However, theoretical solution to the vibration of the rope with vibration suppressors has not yet been obtained. In this paper, a theoretical solution to the free vibration of the rope with vibration suppressors is presented, in the case of that vibration suppressors are arranged at equal intervals. Finite difference analyses of the rope vibration with/without vibration suppressors are also performed. The effect of the number of vibration suppressors on the natural frequency and rope deflection are clarified. The calculated results of the finite difference analyses are in fairly good agreement with the calculated results of the theoretical solution.