Evaluation of Seismic Performance of Steel Lattice Transmission Towers

Abstract

The electricity transmission systems are an important lifeline for modern societies. They are used for overhead power lines as supporting structures. Transmission towers are designed to meet electrical and structural requirements. They are designed according to the weight of conductors and environmental effects such as wind and ice loads. They also considered other extraordinary stresses such as cable breakage and ice-breaking effects. Because of a common perception that transmission line (TL) towers show low sensitivity to earthquakes, the effects of the earthquake in TL tower construction are not considered. For this reason, TL towers are investigated with regard to the seismic performance in this study. The principal objectives of this research are: i) to assess the sensitivity of typical TL towers to earthquake loads, ii) to retrofit an existing steel lattice tower using a new section Centre To Center (CTC). In this study, a finite element model of a representative 154 KV transmission tower in Turkey was performed using a set of 10 recorded earthquake ground movements. The four-legged square TL tower has been analyzed and designed for Turkey, Eskisehir seismic zone considering 42.95 m height using finite element (FE) software. Therefore, a new section Centre To Center (CTC) type has been designed and the failed sections have been replaced with a designed section using the SAP2000 section designer. The results show that the load of failure increased after retrofitting. The retrofitting method was effective and easily conducted in fields. Doi: 10.28991/cej-2020-03091600 Full Text: PDF

Numerical Simulation of Impact Effect on Stability of Transmission Tower Foundation

“…At the same impact time, the uplift value of unit node B is the largest when the impact occurs at the edge position, which means that an impact at the edge position has a significant influence on the deformation of the surrounding soil of the transmission tower foundation. (5). By using reinforcement bars of different strengths, the maximum lateral displacement, maximum vertical displacement, inclination degree, and damage values of the transmission tower foundation are continuously reduced.…”

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Quantification of the Seismic Behavior of a Steel Transmission Tower Subjected to Single and Repeated Seismic Excitations Using Vulnerability Function and Collapse Margin Ratio

“…This provision demonstrates the gaps and limitations in estimating seismic design capability. Furthermore, since the transmission lines spans are large in modern civil engineering construction, the effects of multiple excitations must be carefully considered, and the frequent failures of transmission line tower systems show that the load pattern defined in the codes does not accurately reflect realistic load conditions [24].…”

Study on the Effect of Geometrical Parameters of a Hexagonal Trigger on Energy Absorber Performance Using ANN

“…Structures containing thin-walled elements may be damaged by other types of loading, e.g., cyclic loading-the consequences of which may be disastrous for the load-bearing capacity of the structure. The effects on load-bearing capacity and energy absorption in these cases are described in the following papers [34][35][36][37]. Nowadays, the finite element method is widely used in analysis; with the help of its advanced solvers, it is possible to calculate complex models using fracture of materials or their deformation during dynamic loading modes [38][39][40][41][42].…”