Structural Behavior of Power Transmission Towers

Abstract

This research is concerned with analysis and design of the power transmission towers. Three types of the power transmission towers were considered in this research to investigate their structural behavior. Data have been collected about the types of towers, their usage, and the types of the applied loads. The study concentrated on the 220 kV double circuit’s Wawa- Wadi halfa Transmission Line Project, the three types of the transmission towers has different configurations and same height and conductor tension. SAP 2000 program was used to carry out structural analysis and design of transmission towers under different load cases. The specifications involved were American Standards. Analysis results was used to make a comparison between three types of power transmission towers and to discuss their behavior under different load combination. The results consist of axial forces distribution on leg, displacements, weight due to dead load and elastic buckling. In analysis it was considered 6 buckling modes and was shown significant increment of buckling loads and buckling factors for each transmission tower. The results indicates that displacement increases in direct proportion to height and that the axial force increase in inverse proportion to height, It was shown decrement the buckling load for each transmission tower models by applying dead and lateral load. The structural behavior of the transmission towers varies depending on the change of transmission towers configuration. Finally it was appeared transmission tower (2) was the most efficient configuration of transmission tower model because it was the most economical and lowest in design sections size, weight, member’s density and axial forces distribution on leg.