无水砂卵石地层盾构施工

CONSTRUCTION OF SHIELD STRUCTURE ON WATER-FREE SANDY GRAVEL STRATUM

为降低刀具磨损、尽量减少开仓换刀,无水砂卵石地层盾构施工时,应优先选用不安装滚刀的大开口率刀盘和卵石输出能力强的无轴螺旋,大卵石含量高的地层还应考虑加装大稠度的膨润土液注入系统。宜保持低土压掘进,控制土体改良材料添加量,使卵石能随砂子经螺旋输送机排出。做好同步注浆、盾构配件等环节管理,以保持均衡连续施工。

In order to reduce the cutter wear and the cutter change by opening the chamber, cutter head with large opening ratio and without hobbing cutter and shaftless screw with high gravel output capability shall be preferred during construction of shield structure liquid injection system shall also be considered to on water-free sandy gravel stratum. High-viscosity bentonite be adopted on stratum with high content of large gravel. Low soil pressure excavation should be maintained and the amount of soil improving material be controlled to enable the gravel to be discharged together with sand by the screw conveyer. Synchronous grouting and shield components shall be managed strictly to ensure smooth and consecutive construction.