关键词: 隧洞工程;活动断裂带;抗错段技术;铰接设计;扩挖设计;香炉山隧洞;滇中引水工程;

Abstract: A large number of long tunnels in China inevitably cross active fracture zones and influencing areas.In order to reduce the structural damage of these tunnels due to fault misalignment, various anti-breakage measures are taken.In this paper, a model test study on the effectiveness of three anti-breakage measures was conducted, including articulation design, expansion-buffer design and articulation-expansion-buffer.Taking the Xianglushan tunnel of the Central Yunnan Water Diversion Project as the background, the effects of the above three types of anti-breakage measures were verified and evaluated from the perspectives of internal lining damage, overall tunnel damage and lining strain.The results show that(1) Based on the characteristics of internal damage in the lining structure of the tunnel, the design of hinge joint, expanded excavation and buffer layer can all protect the lining.(2) From the overall distortion situation and crack distribution of the tunnel, the adopt of hinge joint aggravates the overall distortion of the tunnel in the fault zone area but meanwhile alleviates the damage to the lining itself.The design of expanded excavation-buffer layer not only eases the distortion of the tunnel but also mitigates the destruction of lining itself at the same time.What's more, the distortion of tunnel in the design of hinge joint-expanded excavation-buffer layer only happens in the hinge joint, which causes little damage to the lining.(3) In terms of distribution rules of longitudinal strain in the tunnel, the expanded excavation and hinge joint can both reduce the strain of lining, especially the latter one has obvious effect in alleviate lining strain.The relevant research findings can offer a reference to the selection of anti-breakage solutions in actual tunnels crossing active faults.

Key words: tunnel engineering; active fault; resist breakage design; articulation design; expanded excavation design; Xianglushan tunnel; Central Yunnan Water Diversion Project;