Structural Monitoring and Maintenance Volume 11, Number 2, June 2024 , pages 127-148 DOI: https://doi.org/10.12989/smm.2024.11.2.127 |
||
Development of tension estimation method without damper modeling error for cable with damper |
||
Aiko Furukawa, Yuma Sugimachi and Tomohiro Takeichi
|
||
Abstract | ||
Estimating cable tension is important in the maintenance of cable structures, such as cable-stayed bridges. In practice, the higher-order vibration method based on natural frequencies is used. In recent years, dampers have been installed onto cables to suppress aerodynamic vibration. Because the higher-order vibration method is suitable to cables without a damper, the damper must be removed before using this method. Because damper removal is time-consuming and labor-intensive, a previous study proposed a tension estimation method for a cable with a damper based on the natural frequencies, which does not require the damper' s removal. However, the previous method relies on the modeling accuracy of the damper's complex stiffness. The damper design formula, while intended for design purposes, does not consistently reflect the damper's actual complex stiffness. Therefore, the estimation accuracy deteriorates when the damper's actual complex stiffness deviates from the damper design formula. With this background, this paper introduces a novel tension estimation method based on mode shapes, which circumvents damper modeling errors since mode shapes are independent of the damper's complex stiffness. In the numerical verification using 90 models, the proposed method estimated tension accurately with an estimation error within 0.59%. In the experimental verification, the proposed method estimated tension accurately with an estimation error within 4.17% except for one case, while the previous method had an estimation error of 44% when the damper design formula was used. The proposed method was found to be superior to the previous method in terms of accuracy and practicality by numerical simulation and experiment. | ||
Key Words | ||
cable tension estimation; damper; damper modeling; mode shape | ||
Address | ||
Aiko Furukawa and Yuma Sugimachi: Department of Urban Management, Graduate School of Engineering, Kyoto University, Kyotodaigaku-katsura, Nishikyo-ku, Kyoto-shi, Kyoto 615-8540, Japan Tomohiro Takeichi: Kobelco Wire Company, Ltd., 10-1, Nakahama-cho. Amagasaki-shi, Hyogo 660-0091, Japan | ||