Improving the Seismic Resilience of Aerial Substations:
A Case Study of a 315 kVA Transformer Mounted on Two Concrete Poles Located in the Middle of the Line
Past earthquakes have demonstrated that pole-mounted transformers are among the most vulnerable components in power distribution networks. Significant vibrations and rotations experienced by transformers during seismic events can damage accessories such as bushings and compromise the connections of their mounting platforms, potentially leading to transformer slipping or overturning. In most existing aerial transformers, one or both ends of the transformer platform are connected to reinforced concrete poles using friction joints instead of standard bolt-and-nut connections. This study examines the reasons behind the widespread use of friction joints in conventional aerial transformers and investigates the seismic behavior of a 315 kVA two-pole substation located mid-line in a power distribution system. Nonlinear time history analyses indicate that the seismic performance of the frictional connections between the transformer platform and the concrete poles is insufficient, leaving the substation incapable of withstanding design-level earthquakes. To address these deficiencies, a retrofit solution has been proposed and implemented, strengthening the connections of the transformer platform. A comparative analysis of the retrofitted and original configurations demonstrates that the novel retrofitting details effectively limit transformer rotations to less than 0.015 radians during design-basis earthquakes. These enhancements significantly improve the stability and seismic performance of aerial transformers, ensuring greater resilience under seismic loading.
Toopchi-Nezhad, H. (2025). Improving the Seismic Resilience of Aerial Substations:
A Case Study of a 315 kVA Transformer Mounted on Two Concrete Poles Located in the Middle of the Line. Amirkabir Journal of Civil Engineering, (), -. doi: 10.22060/ceej.2025.23376.8154
MLA
Toopchi-Nezhad, H. . "Improving the Seismic Resilience of Aerial Substations:
A Case Study of a 315 kVA Transformer Mounted on Two Concrete Poles Located in the Middle of the Line", Amirkabir Journal of Civil Engineering, , , 2025, -. doi: 10.22060/ceej.2025.23376.8154
HARVARD
Toopchi-Nezhad, H. (2025). 'Improving the Seismic Resilience of Aerial Substations:
A Case Study of a 315 kVA Transformer Mounted on Two Concrete Poles Located in the Middle of the Line', Amirkabir Journal of Civil Engineering, (), pp. -. doi: 10.22060/ceej.2025.23376.8154
CHICAGO
H. Toopchi-Nezhad, "Improving the Seismic Resilience of Aerial Substations:
A Case Study of a 315 kVA Transformer Mounted on Two Concrete Poles Located in the Middle of the Line," Amirkabir Journal of Civil Engineering, (2025): -, doi: 10.22060/ceej.2025.23376.8154
VANCOUVER
Toopchi-Nezhad, H. Improving the Seismic Resilience of Aerial Substations:
A Case Study of a 315 kVA Transformer Mounted on Two Concrete Poles Located in the Middle of the Line. Amirkabir Journal of Civil Engineering, 2025; (): -. doi: 10.22060/ceej.2025.23376.8154
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