| Transmission tower is a kind of high-rise structure and it is erected everywhere. Many disasters caused by wind and earthquake make us believe that if the transmission tower system is destroyed, it will hurt power system and affect people's life. As a result, it maybe draws fire disaster and brings great loss to the property. How to ensure the transmission tower system works normally under any condition is an important study subject in the electric power field and civil engineering field.In this paper, based on the Oujiang 220kV transmission tower system, wind-induced vibration control for a tall steel lattice transmission tower was examined by using a 1:100 full aeroelastic model test and numerical method. In numerical method, two different kinds of model, 3D FEM model and 2D multi-degree-freedom model were used. The main content includes as follows:1) A wind tunnel experiment model and its suspended mass pendulums were designed based on the Oujiang transmission tower.2) The basic characteristics and expression of wind load were investigated. And the time histories of fluctuating wind velocities were generated by Simiu power spectrum according to spatial correlations at various mean wind velocities using triangle series method.3) A 3D beam-truss-mass FEM model was established. The along-wind dynamic responses of the transmission tower were calculated in the time domain. The numerical results show good agreement with the experimental results.4) A multi-degree model was erected based on previous academic references. The optimal design parameters of TMD,VED and MR dampers are also determined in time domain by using this model.5) The performances of some semi-active control strategies for transmission tower with MR dampers were compared. Several important factors which greatly affect the damper's vibration abating performance were analyzed and some valuable conclusions were gained for design of MR dampers.
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