Research On Wind-induced Response Of UHV Guyed Single-Mast Transmission Tower-Line System

The UHV guyed single-mast transmission tower is typical structure of tall and slender, if it can be satisfy the wind resistance design became a hotspot around the engineers who engaged in transmission line engineering. Therefore, The analysis on wind-induced response of UHV guyed single-mast transmission tower is significant.A kind of simplified methods of guyed tower’s structure was presented in this paper, the finite element model of guyed tower-line system was built by the simplified method, the influence of boundary conditions and spans to guyed tower’s wind-induced response was discussed, the wind-induced response of guyed tower was analysed, the influence of guy’s prestress and included angle to the ground to guyed tower’s wind-induced response was further studied, and the wind-induced vibration coefficient of guyed tower was calculated. The contents of this paper as follow:(1) Based on the simplified methods of guyed tower’s structure, the guyed tower’s exact model which consists of beam and truss elements was simplified to the simplified model which only consists of beam column element. The static characteristics, dynamic characteristics and wind-induced responses of two models were contrast analysed. Result shows: The static characteristics, dynamic characteristics and wind-induced responses of simplified model is very close to those of the exact model, this simplified method has a high precision.(2) The difference of spans and boundary conditions were considered, and four kinds of typical tower-line system finite element model were built by the simplified method. The anlysis of their wind-induced response shows that: Four kinds of models’ mean displacements of downwind displacement time history curves and max axial forces of axial forces time history curves are very close. The variances are slightly different.(3) The wind-induced response of one tower and two lines system was analysed, the influences of guy’s prestress and included angle to the ground to guyed tower’s wind-induced response were further studied. Result shows: Under high intensity wind, the guyed tower’s mast produces combined deformation of compression, bending and torsion. And the mast’s vibration is greatly affected by conductor’s vibration. The mast produces downwind rigid body swing vibration and bending vibration, and the downwind rigid body rotation around bottom is the major factor that caused downwind displacements of mast. Both of the mast’s mean displacement and max axial force change nonlinearly with the increase of the guy’s prestress and guy’s included angle to the ground.(4) The computing method of wind-induced vibration coefficient was stated, the wind-induced vibration coefficient of guyed tower was calculated, and the result was compared with code standards. Result shows: The wind-induced vibration coefficient will abrupt changes on transverse, it shuold be careful during design process. The coefficient calculated by time history analysis is very close to that according to GB 50009-2012.