|
Title |
Vision-based Method for Estimating Cable Tension Using the Stay Cable Shape
|
|
Authors |
김진수(Jin-Soo Kim) ; 박재봉(Jae-Bong Park) ; 이덕근(Deok-Keun Lee) ; 박동욱(Dong-Uk Park) ; 김성완(Sung-Wan Kim) |
|
DOI |
https://doi.org/10.11112/jksmi.2024.28.1.98 |
|
Keywords |
사장교; 케이블 장력; 진동법; 영상기반 방법 Cable-stayed bridge; Cable tension; Vibration method; Vision-based method |
|
Abstract |
Due to advancements in construction technology and analytical tools, an increasing number of cable-stayed bridges have been designed and constructed in recent years. A cable is a structural element that primarily transmits the main load of a cable-stayed bridge and plays the most crucial role in reflecting the overall condition of the entire bridge system. In this study, a vision-based method was applied to estimate the tension of the stay cables located at a long distance. To measure the response of a cable using a vision-based method, it is necessary to install feature points or targets on the cable. However, depending on the location of the point to be measured, there may be no feature points in the cable, and there may also be limitations in installing the target on the cable. Hence, it is necessary to find a way to measure cable response that overcomes the limitations of existing vision-based methods. This study proposes a method for measuring cable responses by utilizing the characteristics of cable shape. The proposed method involved extracting the cable shape from the acquired image and determining the center of the extracted cable shape to measure the cable response. The extracted natural frequencies of the vibration mode were obtained using the measured responses, and the tension was estimated by applying them to the vibration method. To verify the reliability of the vision-based method, cable images were obtained from the Hwatae Bridge in service under ambient vibration conditions. The reliability of the method proposed in this study was confirmed by applying it to the vibration method using a vision-based approach, resulting in estimated tensions with an error of less than 1% compared to tensions estimated using an accelerometer.
|