FE Simulation of Transmission Tower

The vital components of the transmission line are the electrical transmission towers. They are commonly used to support the phase conductors and shield wires of a transmission line. Also the accurate prediction of tower failure is very important for the reliability and safety of the transmission system. The current research describes nonlinear FE models of predicting the transmission tower failure. In the current FE simulations, the eccentricity and the joint effect of the tower were considered. The current models have been calibrated with results from previous full-scale tower tests and numerical models with good accuracy in terms of both the failure load and the failure mode. 1. Introduction The common transmission towers systems are the pole system and the lattice system. The pole system can be economically used for relatively shorter span and lower voltage (345-kV or less). It may be wood pole, tubular steel, concrete, or reinforced plastics pole (it is the highest restricting application). On the other hand the lattice system can be used for the highest voltage level. The lattice tower members typically consist of steel or aluminum angle sections. The two types can be self-supporting or guyed [1, 2]. In 2012, Selvaraj et al. [3] discussed experimental studies carried out on transmission line tower made from FRP pultruded sections. The tower must be designed for their own weight, weight of the conductors and insulators, wind, ice (eighty-two transmission towers in the end of November 2005 in Münsterland, Germany failed due to snow rolls formed around the conductors [4]), vibration load, and security load. The security load occurs on the tower due to accidental events such as broken conductors, broken insulators, or collapse of an adjacent structure in the line due to an environmental event such as a tornado. It causes longitudinal loads on the tower [5]. The primary members of the lattice tower are the leg and the bracing members. They carry the vertical and shear loads on the tower and transfer them to its foundation. Secondary or redundant bracing members are used to provide intermediate support to the primary members to reduce their unbraced length and increase their load carrying capacity [2]. The tower members are usually angles or flat bars and they are often directly connected together to eliminate gussets by galvanized bolted joints. Using galvanized bolted joints reduces effectiveness of friction type so that these bolts are bearing type bolts. Additionally bearing type bolts are preferred to friction type because they are easy to erect at