Study On Ice-coating And Ice-Shedding Of 220kV Transmission Tower-Line System And Application Of Large Deformation Bolt Foundation

With the development of the national economy depending on the energy and the state investment in infrastructure in central and western regions, A lot of high-voltage transmission lines are newly building in large scale in our country. Because of the vast area of land, climate is different across different regions; some lines inevitably go through extreme weather conditions such as snow and ice disasters. So the study of the performance of the tower-line system’s deformation in snow and ice weather and the performance of large deformation bolt foundation in tower-line system’s anti-ice disaster, ensuring the tower-line system’s safe operation under extreme weather conditions, has very impotent practical significance.In this paper, a simplified glass-type transmission line tower is built to study the performance of the tower-line system under different conditions of ice-coating and ice-shedding. Variations are summed of the tower-line system form different view point, such as the displacement of conductor’s middle point, the axial stress of conductor, the rod’s stress of different positions of the tower. By comparing the results of simplified model and numerical analysis model, ANSYS model can correctly simulate the tower-line system.Through the establishment of finite element model that contains three towers and four spans, this paper study several aspects of the tower-line system under different ice-shedding load, such as the middle point’s displacement of conductor and ground wire, the axial stress of conductor and ground wire, unbalanced tension of the tower-line system, the rod’s stress of different positions of the tower, support reaction of the middle tower. The research obtains the variations and the most unfavorable position of the tower-line system under different ice-shedding load, which provides suggestions for strengthening transmission lines in service under extreme weather conditions.Combined variation of large deformation bolt and the idea of initiatively reduce the adverse effects of tower-line system under snow and ice weather condition, this paper study different stretched length of bolt affect indicators of the tower-line system under 20 mm ice-shedding load and the bolt applied the middle tower. When the tower-line system apply large deformation bolt foundation, by comparing results, the results show the foundation is good for the rods at the bottom and middle position of the tower, has a complex influence of the beam rods and bracket rods, has little effect on other indicators.