为提升再制造敞开式TBM在软岩隧道中的防卡机脱困能力，以大凉山1号隧道平导为例，通过工程实践对比分析再制造TBM防卡机改造的必要性，提出针对主驱动、支护系统和刀盘扩挖系统的防卡机改造方案。工程实践表明： 1）通过更换主驱动减速机，再制造TBM的额定转矩和脱困转矩可提高38%； 2）护盾和管棚钻机的改造可实现利用护盾导向孔快速施作超前管棚，一体化齿圈可确保管棚钻机和应急喷射混凝土设备的快速移动和准确定位，形成以护盾、锚杆、钢筋排、应急喷射混凝土和钢拱架相结合的连续封闭支护体系； 3）提出边滚刀外移和预留扩挖刀箱的扩挖方案，结合主驱动抬升技术可满足再制造TBM在软弱围岩洞段长距离连续扩挖掘进的需求。通过软弱围岩洞段防卡机处置案例及其整体应用效果，验证了上述防卡机改造方案的可行性及有效性。
A case study on the pilot
tunnel of the Daliangshan No. 1 tunnel is conducted with the aim of enhancing
the anti-jamming and jam-releasing capabilities of remanufactured open tunnel boring machines
(TBMs) in soft rock tunnels. The necessity of anti-jamming
transformations for remanufactured TBMs is analyzed by employing suitable
engineering practices, and transformation strategies targeting the main drive,
support system, and cutterhead over-excavation system
are proposed. The engineering practices demonstrate the following. (1)
Replacing the main drive gearbox reducer increases the remanufactured TBM′s rated and recovery torque by 38%. (2) Modifications to the shield
and pipe-roof drilling machine facilitate the rapid
installation of advance pipe roofs using shield guide holes. In addition, an
integrated gear ring facilitates the quick mobility and precise positioning of
the pipe-roof drilling machine and emergency shotcrete
equipment. These measures result in the establishment of a continuous and
enclosed support system that integrates the shield, rock bolts, steel ribs,
emergency shotcrete, and steel arches. (3) An over-excavation
scheme incorporating cutter edge extension and pre-reserved
over-excavation cutter boxes is proposed. Combined with
main drive elevation technology, this approach facilitates long-distance continuous over-excavation in soft
rock tunnel sections. Finally, field applications confirm the feasibility and
effectiveness of the proposed anti-jamming
transformation strategies.
