泥水盾构长距离穿越高水压破碎带施工技术

Construction Technology of Long-distance Slurry Shield Tunneling through Fracture Zone under High Water Pressure

以青岛地铁8号线大洋站—青岛北站东侧过海段区间的高水压长距离泥水盾构工程为案例,针对盾构长距离穿越富水断裂破碎带施工的特点,从盾尾密封、高压换刀、破碎带稳定、岩层软硬不均、盾构姿态调整等方面,分析其施工难点,并提出了相应的刀盘配置、盾体保压及盾尾密封等盾构机改造措施。阐述了破碎带施工高压换刀、开挖面稳定控制、盾构掘进姿态控制等施工措施,总结了刀盘推力、刀盘扭矩、刀盘转速及掘进速度等现场掘进参数的变化规律。

Taking the high-water-pressure and long-distance slurry shield engineering of the sea crossing section on Qingdao Metro Line 8 Dayang Station-Qingdao North Station east side sea section interval as study case,from aspects including shield tail seal,cutter change under high pressure,stable fracture zone,imbalance of the hard and soft rock layers,as well as shield posture adjustment,targeting construction characteristics of shield long-distance passing water-rich fracture zone,the construction difficulties are analyzed,and corresponding shield machine reformation measures such as cutterhead configuration,shield body pressure maintaining and shield tail seal are proposed.Construction measures for fracture zone including cutter switch under high pressure,excavation face stability control,and shield tunneling posture control are expounded.Change pattern of on-site excavation parameters including cutterhead thrust,cutterhead torque,cutterhead rotational speed and excavation speed are summarized.