A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Soundness investigation of suspender ropes of the suspension bridge which has passed 20 years
Of suspension bridges of the Honshu-Shikoku Bridges, Innoshima Bridge, which is the oldest, was found to have rust and rusty water on the surface of suspender ropes after 16 years of service. To identify corrosion inside the ropes, suspender ropes were sampled and tensile strength test and disassembly inspections were conducted in the plant. The results showed that the ropes had corrosion inside, which could not be detected from appearance. Because it was confirmed that corrosion conditions inside the ropes could not be detected by external visual inspection, we started to develop a nondestructive inspection method to enable the quantitative evaluation of corrosion inside the suspender ropes. Various tests indicated that corrosion inside suspender ropes could be detected accurately by measuring an entire rope continuously by the main flux method. Therefore the practicable main flux method was applied to the suspender ropes of Innoshima Bridge and Ohnaruto Bridge. On-site measurement by this method identified the corrosion details of the two bridges suspender ropes, which differed in paint characteristics and painting method. Comparison between the on-site measurements and laboratory measurements confirmed that this method enabled highly accurate on-site measurement. In addition, disassembly inspection on the suspender ropes of Innoshima Bridge and Ohnaruto Bridge were implemented. The disassembled samples were subjected to such tests as external visual inspection, rope tests, wire tests, and microscopic cross-section inspection. These tests identified the corrosion characteristics in the individual portions, and the rope tests conducted on Ohnaruto Bridge suspender ropes clarified the relationship between the decrease in crosssectional area and strength reduction rate of CFRC suspender ropes, which are commonly used as suspending members of large-scale bridges. The clarification of the relationship between suspender ropes decrease in cross-sectional area and strength reduction rate enables the evaluation of tolerable corrosion limits based on cross-sectional rope strength, making it possible to establish a rational maintenance method for suspender ropes by using continuous measurement by the main flux method as well. To establish a suspender-rope maintenance method in the future, we intend to continue to gather data concerning the tensile strength of corroded suspender ropes, while conducting investigations on the safety requirements of suspension bridges suspender ropes.
Soundness investigation of suspender ropes of the suspension bridge which has passed 20 years
Of suspension bridges of the Honshu-Shikoku Bridges, Innoshima Bridge, which is the oldest, was found to have rust and rusty water on the surface of suspender ropes after 16 years of service. To identify corrosion inside the ropes, suspender ropes were sampled and tensile strength test and disassembly inspections were conducted in the plant. The results showed that the ropes had corrosion inside, which could not be detected from appearance. Because it was confirmed that corrosion conditions inside the ropes could not be detected by external visual inspection, we started to develop a nondestructive inspection method to enable the quantitative evaluation of corrosion inside the suspender ropes. Various tests indicated that corrosion inside suspender ropes could be detected accurately by measuring an entire rope continuously by the main flux method. Therefore the practicable main flux method was applied to the suspender ropes of Innoshima Bridge and Ohnaruto Bridge. On-site measurement by this method identified the corrosion details of the two bridges suspender ropes, which differed in paint characteristics and painting method. Comparison between the on-site measurements and laboratory measurements confirmed that this method enabled highly accurate on-site measurement. In addition, disassembly inspection on the suspender ropes of Innoshima Bridge and Ohnaruto Bridge were implemented. The disassembled samples were subjected to such tests as external visual inspection, rope tests, wire tests, and microscopic cross-section inspection. These tests identified the corrosion characteristics in the individual portions, and the rope tests conducted on Ohnaruto Bridge suspender ropes clarified the relationship between the decrease in crosssectional area and strength reduction rate of CFRC suspender ropes, which are commonly used as suspending members of large-scale bridges. The clarification of the relationship between suspender ropes decrease in cross-sectional area and strength reduction rate enables the evaluation of tolerable corrosion limits based on cross-sectional rope strength, making it possible to establish a rational maintenance method for suspender ropes by using continuous measurement by the main flux method as well. To establish a suspender-rope maintenance method in the future, we intend to continue to gather data concerning the tensile strength of corroded suspender ropes, while conducting investigations on the safety requirements of suspension bridges suspender ropes.
Soundness investigation of suspender ropes of the suspension bridge which has passed 20 years
Untersuchung der Fehlerfreiheit von Hängeseilen an Hängebrücken die älter als 20 Jahre alt sind
Nakamura, M. (author) / Saito, T. (author) / Sugimoto, T. (author)
2004
8 Seiten, 8 Bilder, 4 Tabellen, 2 Quellen
(nicht paginiert)
Conference paper
Storage medium
English
Soundness investigation of suspender ropes of the suspension bridge which has passed 20 years
| British Library Conference Proceedings | 2004
| British Library Conference Proceedings | 2002
Development of a new nondestructive inspection method for suspender ropes of suspension bridges
| British Library Conference Proceedings | 2013