Experimental Study of Torsion of Guyed Mast Shaft

摘要

The torsion of the mast shaft has been monitored on several masts in the Institute of Theoretical and Applied Mechanics (ITAM) since 2005. The occurrence of this phenomenon is conditioned by the fact that the guy ropes are attached out of the axis of the mast shaft. An experimental mast-shaft model of 15 m height guyed in 3 directions was used for the more detailed study of its rotational motion. The excitation was realized by transversal auxiliary rope drawn by harmonic human force in resonance. The displacement of the shaft top results in translation caused by the guy force and the rotation, caused by the eccentricities of the guy-ropes, attached out of the shaft axis. The resulting movement of the shaft support is an elliptical orbit. The shaft of our experimental mast was equipped in two levels with accelerometers for registration of horizontal x, y motions. The two x, y signals in two levels were monitored and analysed.