Identification of cable tension of long-span cable-stayed bridges during super typhoons: A case study

Cables have currently surpassed lengths of 570 meters on long-span cable-stayed bridges, potentially resulting in large amplitude vibrations in complex engineering situations especially under typhoons. Therefore, identification of time-varying cable tension during super typhoon is of great significance for ensuring the systemic safety of bridges. To address this issue, this paper aims to track the time-varying tension of cables during the typhoon event. An algorithm is utilized to extract the variation trend of typhoon-induced tension based on vibration theory. Structural health monitoring data of a long-span cable-stayed bridge during a super typhoon is taken as a case to verify the algorithm. The instantaneous fluctuations in tension of six cables are clearly reproduced. Meanwhile, the other monitoring data, including stress and structural displacement, is synchronously displayed to show the correlation of monitoring parameters. The results show that the proposed method has the potential to real-time identify and assess the cable tension of long-span cable-stayed bridges under super typhoons.