The Ultimate Load And Dynamic Analysis Of Transmission Tower Frame

Transmission tower frame is one kind of space structure used in power industry to support transmission lines. And its stability weighs heavily against the safety of transmission lines. With the great power needs of our national economy, our country has invested much on power construction to promote the power output. At present, lots of transmission towers with great span and high-voltage come out. Besides, with the deterioration of nature environment, exceedingly severe weather occurs frequently, such as hurricane, violent storm, heavy snow and so on. And whether transmission towers can endure the exceedingly bad weather becomes our great concern. So, to study the ultimate load and dynamic response of transmission towers under the given loads case is very important both in theoretical research and engineering practice.Nowadays, most mechanical behavior analysis of transmission towers is in the domain of elasticity, and has nothing to do with plasticity. In this dissertation, rigid frame model appropriate for ultimate load analysis is established according to the existing study and corresponding design data. Geometry nonlinearity and material nonlinearity are also taking into consideration in this paper. In the model, the static wind force is applied by APDL precisely, and ultimate wind force analysis along three directions is conducted. The results obtained indicate that the tower structure member bars are controlled by different kinds of load. In order to increase the ultimate load of transmission towers, the main bars near the foot of transmission towers should be reinforced firstly. Eigenvalue buckling and mode analysis are also conducted, from which corresponding character parameters are obtained. Finally, pulsating wind time-procedure analysis along the 0 wind direction is conducted. In the time-procedure analysis, the pulsating wind spectrum is simulated according to Davenport spectrum, and dynamic response of transmission towers induced by pulsating wind is obtained. Compared with the ultimate static wind load analysis, pulsating wind can bring more damage to the transmission towers.In the dissertation, ultimate load analysis and dynamic response analysis of transmission towers are conducted. For the reason that the model of complex environment load is still under discussion, many aspects, such as specific ultimate load and tower-line coupled vibration, still need more further research.