The impact of climate change on typhoon-induced dynamic response of transmission tower-line system: A case study in Hong Kong

The impact of typhoon wind loads on electric transmission networks is becoming increasingly significant, often leading to the failure of overhead transmission tower-line systems. This study aims to provide insights into the typhoon wind field caused by climate change scenarios, as well as the typhoon-induced dynamic loads and the attendant response of the transmission tower-line system through numerical simulations. Utilizing sea surface temperature (SST) as the marker of climate change, this study assesses the performance of future typhoons under historical conditions (1961–2020) and three Shared Socioeconomic Pathways (SSPs) from 2021 to 2080: SSP1–2.6, SSP2–4.5, and SSP5–8.5 scenarios. Simulations involving stochastic wind loads and the finite element-based structural analysis suggest that rising SSTs notably increase wind-induced maximum stresses and axial forces within the system components, thereby increasing the transmission towers’ structural demands. Specifically, under SSP5–8.5—the most extreme climate scenario—the maximum stress increases to 162.88 MPa (6.92% increase), while axial forces reached 1189.27 kN (32.20% increase) compared to the historical climate, and tension at the midpoints of ground wires reached 87.59 kN (∆=68.77%). Furthermore, the top maximum displacement of transmission tower is 0.22 m (∆=63.37%) for SSP5–8.5 compared with the historical scenario, highlighting the growing vulnerability of the transmission tower-line system to climate change. These findings emphasise the need for the possible integration of climate change projections into the design, maintenance, and operational strategies of transmission systems against the severe natural hazard events driven by climate change.