Shaking table test on 1000 kV angle steel transmission tower

To analyze seismic response characteristics of 1000 kV angle steel transmission tower and the impact of the qualities of conductors and ground wire on dynamic response of tower structure, shaking table tests were carried out. Under four types of input ground motions the seismic response testing for single-tower with and without lumped mass that equals to the sum of all mass of conductors and ground wires under seismic intensity 8 were performed and compared. Experimental results show that the first natural vibration frequencies of the tower with lumped mass was reduced by 2% in the direction along the transmission line and by 17% in the direction transverse the transmission line than those of the tower without lumped mass in the two directions. For the tower structure using V-shaped suspension mode of insulators the impact of both connection mode of insulators and conductor mass should be considered in the calculation of the dynamic property of the tower in the direction transverse transmission line. Due to the longer cross arm of 1000 kV transmission tower and the smaller height-width ratio of the cross arm, there is evident space coupling in the seismic response, so under the action of earthquake the torsion vibration mode would contribute a lot to the dynamic responses. In general, the mass of conductors is favorable to anti-earthquake of transmission tower, and during dynamic analysis on the tower-conductor system it is more reasonable to consider the impact of the mass of conductors in the evaluation of internal force of structural members.