Study On Wind-induced Dynamic Response Of Tension-resistant Transmission Tower-line System Under Multi-climate

The transmission tower-line system is the backbone of the transmission line and an important lifeline project.Due to the low natural frequency of the transmission tower line system,it is very close to the excellent frequency of the wind.Under extremely complicated weather conditions and certain special working conditions,the tower may break or even continuously collapse.Due to the complex mechanism of tower-line coupling,there are still many difficulties in theoretical analysis.The most effective method is to analyze through numerical simulation methods to obtain the wind-induced dynamic response characteristics of the tower line structure system,provide effective theoretical guidance and direct design basis for the wind resistance design of the transmission tower line system,and ensure the safe operation of the transmission line equipment.It is of great significance to reduce the loss of people's property and protect the order of people's lives.This article takes a tension tower line as the research object,based on the basic theory of wind engineering,establishes a tension tower line system analysis model,analyzes the dynamic characteristics of single tower and tower line systems,and understands the dynamic characteristics of the structure itself.On this basis,the wind-induced dynamic response characteristics of the tension tower line system under various kinds of climate are studied by simulating the dynamic effects of normal wind load,combined wind and rain excitation load and moving downburst wind load.Through research,it is found that the influence of the transmission line on the system is directional.Outside the plane of the tower line,the wire does not contribute much to the rigidity of the tower.Due to the increase in the overall mass,the rigidity of the tower in this direction is small,and the coupling effect of the tower line is on the tower line.The out-of-plane direction is more prominent,and under the action of incoming wind,the resonance response of the tower line out-of-plane direction has occurred many times before reaching the vibration frequency of the tower body.When considering rainfall,the combined excitation of wind and rain under heavy rain and strong weather has a significant effect on the displacement of the top of the tower,and the increase amount even reaches about 20% under extreme conditions.It should be considered in the relevant power design.The peak displacement and acceleration power spectrum values are much greater than the normal wind,and the frequency corresponding to the spectrum peak has moved forward.The impact of the downburst on the dynamic response of the transmission tower line system is more significant than that of the normal wind.