| The development of special high-voltage transmission technology is one of the most significant technology policys of the Eleventh-five National Key engineering project, while it is the climbing plan to surpass the world's advanced level in power and civil areas, whose construction will have significant function to our country's sustained economic development. As the support body of special high-voltage transmission line, the tower-line system is a strong non-linear coupled system, which is composed by wire, insulators and power transmission towers, while the long-span is a special case across great rivers. Long-span transmission tower is a high flexible structure, it is sensible to dynamic load, especially to wind, which would easily generate significant dynamic response. It is an important researching subject for both power engineering and civil engineering to control the vibration of long-span transmission tower due to its important theoretical meaning as well as economical value.In order to provide a guide of the reasonable methods in natural vibration period and wind-induced vibration control, the dynamic characteristics, the numerical simulation of wind load, the research and development of lead-rubber damper, the effect of wind-induced vibration control and its verification, the seismic response deserve special attention. Consequently, study on the following aspects would be included in this dissertation.(1)Delicate modeling programs have been studied for long-span transmission tower-line system using finite element method, focusing on different treatments of the poles and nodes. Based on modal identification techniques, the natural vibration period of transmission tower in tower-line system were obtained for two different types, while the stiffness and weight of transmission line and insulator were considered. The natural vibration period and mode shapes of the towers in simplified model and bundle conductors model were researched, the former can be used to simplify the latter to execute a variety of dynamic response analysis.(2)A simulation program WVFS has been compiled to simulate applicable fluctuating wind velocity field in this paper. The examination was carried on from the detailed derivation of average value, correlation function, power spectral density and root variance. According to the research on simplified method of the electric power industry, it could be got that there are little differences between the displacements derived here by FELM time history method and that derived by simplified method, which means that the simulation on space relevant wind velocity field are reasonable.(3)The lead-rubber damper (LRD) was developed, while its working principle and structure were introduced. According to the performance testing, the loading frequency, strain amplitude, lead diameter and durability were considered, the formula for parameters of LRD were derived. According to the research on optimalizing location of LRD, the specific installation scheme was obtained. The connection and installation methods, the impact on the structure were discussed.(4)The time history analysis method was used to calculate the response of the wind-induced response of long-span transmission tower-line system. According to the research on the displacement and internal force of the main material under five wind directions, the effects of wind-induced vibration controlling were obtained. The most disadvantageous wind direction of the displacement and inner force are not always identical, so the different input wind direction in engineering design should be considered. Dynamic wind in different directions would lead to both transverse and longitudinal vibration of the tower. Besides, the adjustment factors along wind were obvious decreased, while the dynamic reliability has improvement in a certain extent.(5)The sensitivity of the controlling effect and the practicality of LRD were researched for long-span transmission tower-line system. According to the research on the deformation, stiffness and damping effect of LRD, the controlling effect is verified. The response and controlling effect of displacement and acceleration in transverse and longitudinal would be affected by tower height and tension of transmission lines. It is also proved that all the LRD are ensured to work under design wind velocity according to the research on LRD deformation; it is also proved that the controlling effect is not ideal when only member stiff is increased according to the research on controlling effect under dynamic wind when apply only stiff to the members on which the dampers used to be applied.(6)The time history analysis method was used to calculate the response of the seismic response of long-span transmission tower-line system. It is shown that the seismic displacement response is far less than dynamic wind, which means it should be based on dynamic wind loads in the design work. Due to the seismic displacement response is very small, the controlling effect is not ideal.
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