Integrated track-bridge management method for large-span railway suspension bridges based on train operation performance

A management methodology and indicator system are expected to be established for track geometry on large-span suspension bridges to address the shortcomings of existing track management criteria in bridge and track maintenance. Taking a suspension bridge with a main span of 1 092 m as the research object, a vehicle-track-bridge coupled dynamic analysis was conducted to investigate the influence rule of bridge deformation-induced track geometry evolution on the operation of high-speed trains on the bridge. The cutoff wavelength for smoothness management of track geometry was also identified. Based on a wavelength separation approach, the track irregularities were distinguished from the dynamic longitudinal profile of the bridge. A unified indicator system applicable to large-span suspension bridge scenarios was proposed in reference to the management standards of conventional railway lines. Furthermore, a quantitative analysis was performed to evaluate the contributions of different track geometry components to car body acceleration. Research results show that a cutoff wavelength of 120 m can be adopted for track smoothness management on long-span bridges. Based on this cutoff wavelength, an effective separation between track irregularities and the dynamic longitudinal bridge profile can be achieved, enabling the track management indicators for large-span suspension bridges to be unified with those of conventional railway lines. According to ride comfort limits, the management thresholds for track irregularities and bridge longitudinal profiles can be determined. An integrated track-bridge management framework can thus be established for large-span railway suspension bridges, providing guidance for their design and operation.