Evaluation of track long-wave vertical irregularity on Fuchun River super large bridge

Acceptance standard of long-wave static irregularity for ballastless track of high speed railway adopts 300 m baseline length method which limit is 10 mm. However, this index is hard to satisfy due to the influence of temperature load and secondary dead load as well as creep or other factors which can cause large vertical deformation on the bridge over 200 m. At present, it ’ s necessary to adopt appropriate method of evaluation of track long-wave static irregularity for the development of long-span bridge and track engineering which is different from the current vector distance difference method. The research on the 300 m baseline length and 60 m midpoint chord measurement long-wave static irregularity of Fuchun River bridge, (30+46+300+97+62.395) m composite steel-concrete beam cable-stayed bridge, wass studied in this paper which considered theoretical vertical deformation, measured values of track elevation and measured values considering disadvantage temperature condition. The above condition results of long-wave static irregularity respectively are 69.07 mm, 63.56 mm for 300 m baseline length and 6.73 mm, 6.56 mm for 60 m midpoint chord. The research shows that 300m baseline length long-wave static vertical irregularity can’ t satisfy 10 mm limit value, while 60 m midpoint chord measurement can meet its 7 mm limit value on theoretical vertical deformation and measured values conditions. It is suggested that acceptance standard for ballastless track long-wave static irregularity of Fuchun River bridge adopts 60 m midpoint chord measurement and its limit value should be 7 mm which provides reference for the long-wave static vertical irregularity acceptance standard of ballastless track on the large bridges over 200 m. © 2022, Central South University Press. All rights reserved.