Foundation problems of the transmission lines in high latitude permafrost regions and countermeasures: A case study in Northeastern China

Transmission lines in extremely cold high-latitude permafrost regions in Northeastern China face the possibility of severe freeze-thaw disasters, particularly in the area from Jagdaqi to Mo’he. Comprehensive field investigations and aerial surveys were used to investigate these events with the aim of identifying the problems and clarifying the freeze-thaw mechanism, and to propose effective mitigation measures. The most significant challenge was found to be frost jacking, which poses a considerable risk to transmission line stability; mitigation strategies include the design of a flexible device to mitigate its effects. The study provides valuable insights and guidance for the maintenance, operation and sustainable management of transmission lines in permafrost regions globally.