为解决铁路隧道洞内绿色、智能化施工问题，结合天陇铁路腰坡隧道，首先，提出5种装配式仰拱结构设计形式，对吊装孔布置开展受力测试与理论计算分析对比； 其次，对不同车辆荷载作用下结构受力、纵向张拉关键工艺进行测试分析，对仰拱预制块与拱墙连接接头进行模型试验研究，并开展基底注浆试验和拼装试验研究； 最后，结合工程实施，开展装配式仰拱结构受力测试。研究结果表明： 1）单线铁路隧道采用仰拱及填充一体开孔双立柱方案，吊装孔横向间距为4.6 m，纵向间距为0.9 m，起吊加速度控制在0.2 m/s2以内，可以满足起吊安全和实际施工需求； 2）在施工及仰拱拼装机等不同工况荷载作用下，仰拱预制块结构应力均在容许范围内，满足安全性要求； 3）装配式仰拱结构与拱墙现浇结构采用V形接头能较好地满足预制便捷性和安全性，仰拱预制块纵向拉紧力达到373 kN时可完全拉紧； 4）采用装配式仰拱结构，洞内综合施工效率可提高50%以上； 5）工程实际测试表明，采用装配式仰拱结构基底接触压力分布更加均匀，装配式仰拱和现浇拱墙结构作用下，装配式仰拱结构引起拱墙结构受力变化不大。
Green and intelligent construction practices are a current trend in railway tunnels. This study investigates the mechanical properties of prefabricated inverted arch structures during construction using the Yaopo tunnel of the Tianshui Longnan railway as a case study. First, five design modes for these structures are proposed. The modes are then subjected to force tests and theoretical calculations to evaluate the layout of hoisting holes. Next, the structural forces and longitudinal tension under different vehicle loads are tested, and model tests are performed on the connection joints between the prefabricated inverted arch blocks and the cast-in-place arch walls. In addition, tests on foundation grouting and assembly are conducted, and the forces acting on the prefabricated inverted arch structure are validated through practical engineering applications. The results reveal the following: (1) The integral opening double-column scheme for the inverted arch and filling of single-track railway tunnels meets the hoisting safety and construction requirements, with hoisting hole horizontal spacing of 4.6 m, longitudinal spacing of 0.9 m, and a controlled hoisting acceleration of 0.2 m/s2. (2) The structural stress of the prefabricated inverted arch blocks remains within acceptable limits under varying construction and assembly machine loads to meet the safety requirements. (3) The V-shaped joint between the prefabricated inverted arch and the cast-in-place arch wall enhances prefabrication convenience and safety, enabling complete tightening of the prefabricated inverted arch blocks at a tension stress of 373 kN. (4) The use of prefabricated inverted arch structures improves overall construction efficiency within the tunnel by over 50%. (5) The contact pressure distribution beneath the inverted arch base is more uniform with prefabricated structures, and the force variation in the arch wall due to the prefabricated inverted arch structure is minimal.
