【摘要】 研究目的：鉴于传统隧道施工方案工期较长且既有大跨隧道施工方案无法较好保证超大断面大跨衬砌施工稳定性和工程经济性，以苏州国际快速物流通道二期工程七子山隧道工程为案例，探索连拱隧道与大跨隧道两者同时开挖施工来缩短工期的可能性，同时研究超大断面大跨隧道的创新施工技术。研究结论：（1）针对连拱隧道向大跨隧道的转换，提出基于横通道的分步扩挖和弧形导坑开挖工艺，通过分阶段初期支护实现围岩应力释放和衬砌结构稳定性，监测结果显示围岩变形显著受控，施工安全性得以保障；（2）在超大断面大跨隧道施工中，采用十二导洞双侧壁导坑与CRD工法并结合多层初期支护的创新施工技术，通过分阶段开挖和动态支护增强围岩稳定性，监测数据表明沉降和水平变形均被有效控制，确保了大跨度隧道的施工安全和质量；（3）本研究结果可为连拱连接大跨隧道工程提高效率和超大断面大跨隧道的安全施工提供参考和借鉴。更多还原

【Abstract】 Research purposes: Given that traditional tunnel construction methods are associated with long construction duration and that existing large-span tunnel construction methods are unable to effectively ensure the stability and economic feasibility of the construction of large-section, large-span linings, this study takes the Qizi Mountain Tunnel of the Suzhou International Rapid Logistics Channel Phase II project as a case study. It explores the feasibility of concurrently excavating the multi-arch tunnel and large-span tunnel sections to shorten the construction period, with the parallel aim of investigating innovative construction technologies for large-section, large-span tunnels.Research conclusions:(1) For the conversion from multi-arch tunnel to large-span tunnel, a stepwise excavation method based on cross passages and a curved pilot tunnel excavation technique are proposed. This approach, coupled with phased initial support, facilitates the release of surrounding rock stress and ensures the stability of the lining structure. Monitoring results indicate that the deformation of the surrounding rock is effectively controlled, ensuring construction safety.(2) In the construction of large-section, large-span tunnels, an innovative construction technique combining twelve pilot tunnels, dualsidewall guide tunnels, and the CRD method with multi-layer initial support is employed. Phased excavation and dynamic support are used to enhance the stability of the surrounding rock. Monitoring data shows that both settlement and horizontal deformation are effectively controlled, ensuring the safety and quality of large-span tunnel construction.(3) The results of this study provide valuable reference and guidance for improving the efficiency of multi-arch to large-span tunnel connections and ensuring the safe construction of large-section, large-span tunnels.更多还原