隧道二次衬砌拱部预制管片顶升机构设计与应用

Design and Application of Jacking Structure for Precast Segment of Arch of Tunnel Secondary Lining

为满足隧道二次衬砌拱部预制管片的安装要求,将预制管片安全便捷地转移至管片拼装小车,基于现场边界条件及施工方案,结合优化设计理念,设计一种专用顶升机构。对顶升机构的结构方案、升降油缸选型进行详细阐述,并分析验证顶升机构升降油缸的稳定性。借助力学方法分析确定顶升机构的最佳安装位置,同时采用有限元方法对边墙衬砌台车门架系统进行强度校核。目前,该顶升机构已在重庆铁路枢纽东环线胡家沟隧道工程得到施工应用,共计辅助完成11组预制管片的拼装作业。理论分析及现场应用表明:1)该顶升机构设计合理,强度及稳定性满足现场施工要求;2)顶升机构投入使用期间,未出现故障,保障了拱部预制管片拼装作业的顺利进行。

The special jacking structure is constructed based on the field boundary conditions, construction scheme, and optimization design concept to achieve the installation requirements of precast segments in the arch of tunnel secondary lining and the transfer of precast segments to segment assembly trolley safely and conveniently. Furthermore, the structural scheme of the jacking structure and the lifting cylinders′ selection are discussed in detail, and the stability of the jacking structures′ lifting cylinder is examined and verified. Finally, using mechanical analysis, the suitable installation position of the jacking structure is identified, and the strength of the sidewall lining gantry system is verified utilizing the finite element method. The jacking structure is currently used on the construction site of the Hujiagou tunnel project of the Chongqing railway hubs′ eastern loop line, where it is assisting in the assembly construction of 11 groups of precast segments. The following points show the theoretical analysis and field application:(1) The jacking structure is well-designed, and the strength and stability can achieve the requirements of onsite construction.(2) There is no malfunction of the jacking structure during the appropriate period, ensuring that the precast segments of the arch are assembled smoothly.