Seismic Analysis of Transmission Tower Line Systems

Electricity is one of the most important necessity of any growing economy. The transmission tower line system consisting of transmission towers and conductors are the main element of an electrical system. Failure of this system leads to greater economic loss. However most of the researches are concentrated on static load, impulsive load and wind loads but not on seismic effects of the system. This study mainly focuses on the seismic behaviour of the combined system of transmission towers and conductors. The model is created based on Indian standard codes. A three tower model connected by cables are used for analysis as they give more realistic results than a single tower model. Four basic towers 66, 132, 220 and 400 kV are created in SAP2000 and time history analysis is conducted on these models to study their seismic behaviour. Analysis is also conducted to find out their behaviour under critical conditions of seismic loading.