Shaking Table Tests of a Reduced-Scale UHV Transmission Tower-Line System Subjected to Near-Fault Ground Motions

Abstract

An ultra-high voltage (UHV) transmission system offers higher bulk capacity and transmission over longer distances compared with conventional transmission systems, and the dynamic responses of such systems have attracted the interest of researchers. This paper focuses on an experimental investigation of the seismic performance of a 1000 kV UHV transmission system subjected to near-fault ground motions. To reproduce the genuine structural responses, a 1:25 reduced-scale experimental model was designed and constructed based on Buckingham’s theorem. Four kinds of typical natural seismic records were selected, namely, far-field, pulseless near-fault, forward-directivity near-fault and fling-step near-fault ground motions, and shaking table tests were subsequently carried out. Furthermore, the influences of the coupling effect between towers and lines, two-component ground motions, and the near-fault effect on the seismic response were investigated. The results demonstrate that the above three factors have a significant influence on the structural response and should not be neglected in seismic analysis. This research enriches the available experimental data and provides a more comprehensive understanding of the seismic performance of UHV transmission systems.