南宁地铁5号线“泥水+土压”双模式盾构掘进模式快速转换关键技术

Key Technology of Rapid Conversion of Slurry/Earth-pressure Dual-mode Shield Tunneling in Nanning Metro Line No.5

以南宁地铁5号线五新区间为工程背景,对并联式双模盾构掘进模式快速转换技术进行介绍。并联式双模盾构"土压+泥水"平衡掘进模式均可以独立运行。掘进过程中采用双模式盾构2套出渣系统相配合的方式改变舱内渣土性状,以满足螺旋输送机和泥浆管道出渣要求,进而启动相应模式下渣土改良方式完成掘进模式转换。通过以上措施双模式盾构完成计划内模式转换2次、试验性掘进模式转换12次,共计14次,未出现明显螺旋输送机喷涌或泥浆管道堵塞的情况,地表沉降控制良好。

The rapid tunneling mode conversion technology of parallel dual-mode shield used in Wuyi Overpass Station-Xinxiu Park Station Section on Nanning Metro Line No.5 is introduced.The slurry mode and earth-pressure mode of the dual-mode shield can be available separately.The cooperation of two series of mucking system can improve the soil in chamber to meet the mucking requirement of screw conveyor and slurry pipe,which can guarantee the mode conversion by soil conditioning.Two times of mode conversion of the shield have been conducted within plan,and 12 times of experimental mode conversion have been conducted;no slurry gushing of screw conveyor of slurry pipe block occurs,and the surface settlement has been effectively controlled.