Research On Seismic Response Analysis And Seismic Control Of Transmission Tower-line System

Towers with large crossing transmission lines are high-rise and long span structural, which are important lifeline engineering. Its security is directly related to the country's economic construction and people's normal life, so it is an important subject for power engineering and civil engineering to ensure the safety of transmission tower-line system. In addition to static load, transmission tower was mainly affected by dynamic load most of the time. The seismic load is one of dynamic loads. Under the seismic action, due to the interaction of tower and power lines, transmission tower-line system form a complex space coupling system. It is often very serious once the system damaged. At present, the study on damping control of transmission tower-line system is mainly concentrated in the aspect of wind vibration control. Therefore, it is necessary to study seismic response analysis and damping control of transmission tower-line system.With ANSYS, a finite-element-method program, it is established a new analytical numerical model combining beam and truss element taking Henan miping transmission tower-line system enovation engineering. Firstly, transmission lines form-finding program is developed and the nonlinear static calculation r esults are taken to be the initial states of the follow-up work. Then, dynamic characteristics of the transmission tower-line system and single towers are analyzed by subspace iteration method. Through the contrast analysis, it is obtained that vibration model of the transmission tower-line system are extraordinary close, and majotity is cable's vibration modes. The mechanism of action how transmission line influences transmission tower is discussed by decomposing transmission line's mass and stiffness.In addition, the time history analysis method is used to research single tower and transmission tower-line system's seismic response characteristics under three different seismic waves. It reveals that the coupling laws how transmission line influences transmission tower through comparing the results of the analysis. Finally, preliminary discussion on seismic control research of transmission tower-line system was carried on. The article analyzed transmission tower-line system's response characteristics with Tuned Mass Damper which installed in the tower head under earthquake. The optimal frequency and optimal damping ratio of the structure were calculated before the analysis. Analysis results show that taking Tuned Mass Damper as the measures of vibration control of transmission tower-line system is feasible.