Numerical investigation on the effect of member orientation to the strength of transmission tower

Loading...
Thumbnail Image
Date
2019-06
Authors
Karen Yong Bee En
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Transmission tower is made up of angle sections that are connected eccentrically by one leg of the section. Generally, commercial software automatically generates the connection of the member as concentric. This type of modelling ignores the actual orientation of the tower members. The eccentric connection may increase the internal forces and need to be investigated. In this study, numerical model of 132 kV transmission tower was generated and analysed with the aid of STAAD Pro. V8i commercial software. The aim is to investigate the change in the member forces and used capacity of main tower members due to eccentric connection. Two types of models were developed to differentiate the members with concentric and eccentric connection. In addition, normal loading condition and another three sets of broken wire conditions were applied to all models. The differences in the member axial forces were calculated and discussed accordingly. The results showed that the axial force in the main members increased under normal loading condition when the wind direction was applied in x-axis. Compared to normal loading condition, models with broken wire condition showed higher increase in the axial forces due to eccentric connection. In addition, the highest percentage differences in terms of maximum compressive force between concentric and eccentric connection was developed in (G.W) broken wire condition subjected to wind in x-axis. Moreover, one of the members located on the tower cage failed when subjected to (T.C + M.C) broken wire condition. In this case, the used capacity was exceeded by 6.82%. The significant increase in the internal member forces and possible failure of tower member due to eccentric member connection suggests that the actual orientation of the tower members must be considered in the design of transmission towers.
Description
Keywords
Citation