In conventional designs of tunnel lining, the finished complete tunnel ring is taken in the design model without considering the unfinished states as a complete ring under water and earth pressure. However, for super large diameter tunnel under difficult tunneling conditions, the segment assembly process will produce complex pre-deformation and loads on the lining. These unfavorable effects are closely related to the configuration of joints and tunneling process. Without proper theoretical guidance, cracks and leakage will appear during or after segment assembly, thus resulting in detrimental effects on long-term performance and durability of the tunnel lining. An analytical method considering all steps from the first segment assembly to the last are established, in which the misplacements and tolerance of bolt holes between two rings are introduced. An exemplified analysis is provided to demonstrate the mechanical behaviors of tunnel lining during the segment assembly under typical deformation conditions, in order to provide guidance for optimizing the tunnel lining design, segment manufacture and tunnel construction.
传统的常常将拼装完成的整环衬砌承受水土等外部荷载作用视为最不利工况，但隧道衬砌均要经历成环前拼装及成环后承受外部荷载作用等两个阶段，每个衬砌环所产生隧道变形又构成了后续衬砌环拼装的先期变形条件。特别是对于超大直径管片隧道 或在较为困难的施工条件下，较大的先期变形将对隧道拼装内力产生显著影响。显然这 种影响与管片接头构造及施工过程密切相关，不合理的设计与施工可导致管片碎裂、渗水等现象而影响隧道的长期使用与耐久性。针对这种情况，对盾构管片衬砌的整个拼装成环过程进行力学解析，并在计算中创新性地引入环间螺栓孔错位的影响。通过计算实例分析一般变形条件下管片分步拼装成环阶段的基本受力特点，以期可以据此优化盾构 隧道衬砌结构与构造设计、管片制作及拼装施工控制等，提高隧道衬砌环的施工质量。