Analysis and Design of Four Legged Transmission Tower

Transmission line towers carry heavy electrical transmission conductors at a sufficient and safe height from ground. In addition to their self-weight they have to withstand all forces of nature like strong wind, earthquake and snow load. The main objective of this paper is to determine the most economical section of tower and its configuration as per Indian Standard IS-800. The present work describes the analysis and design of four legged self-supporting 220 kV double circuit steel transmission line towers models with an angle, tubular and channel sections. In this study dead load and wind load as per IS 802 (1995) are taken into account in these three models. STAAD. Pro program has been used to analysis and design the members of 220 kV double circuit tower. A comparative study is conducted with respective to axial forces, deflections, maximum sectional properties, critical loading conditions between these three models of tower. The study shows that tower with angle sections are most economical and effective section compared to other two sections. The transmission tower has a height of 40 m and square base width of 11.5 m. The members are also grouped for better fabrication. Steel optimization has been carried out to find the most suitable and economical section for the design.