Abstract

Bridge bearings easily suffer damage when exposed to various loading and environmental changes during their lifetime. This effect can have a considerable impact on the bridge service performance, and bearing replacement should be performed if damage occurs. Compared with highway bridges, bearing replacement for long-span bridges under operating high-speed railways (HSRs) is more challenging due to the higher safety requirements for the operation of trains, the larger jacking reaction forces for single piers and the complex bearing structures. In this paper, the defects of bearings in five larger-scale HSR bridges are investigated through field detection, followed by a bridge jacking scheme that includes a temporary support with a continuous height adjustment, a large bearing capacity and good stability. Finally, a replacement method using the invented temporary support and a developed reverse disassembly or assembly technology as well as safety monitoring is proposed and implemented on the bridge. The results show that most defects are caused by the problems remaining from bearings installation, which are aggravated during a long service period, and that the proposed jacking scheme is feasible, which sheds light on the maintenance and replacement of bearings for long-span bridges under operating HSR networks.

摘要

桥梁支座在其使用寿命期间暴露于各种载荷和环境变化时很容易受到损坏。这种影响会对桥梁的服务性能产生相当大的影响，如果发生损坏，应更换轴承。与公路桥梁相比，由于对列车运行的安全性要求更高、单墩顶升反力较大、承重结构复杂，高铁运营下大跨度桥梁的支座更换更具挑战性。本文通过现场检测对5座大型高铁桥梁支座的缺陷进行了调查，提出了一种具有连续调高、承载能力大、稳定性好的临时支座的顶桥方案。最后，提出了一种使用本发明的临时支架和开发的反向拆卸或组装技术以及安全监测的更换方法，并在桥梁上实施。结果表明，大部分缺陷是由支座安装遗留问题引起的，在较长的使用期内会加剧，提出的顶进方案是可行的，为大跨度桥梁支座的维护和更换提供了启示。运营高铁网络。