孤石发育地层盾构下穿房屋关键技术研究

Study on Key Technology of Shield Undercrossing Buildings in Boulder Development Strata

镇龙南站~镇龙站左线区间出镇龙南站之后下穿多栋房屋,房屋主要为2~5层砖混结构民宅。盾构下穿房屋段隧道范围地层以花岗岩残积土及全风化花岗岩为主,存在大量孤石,在掘进过程中存在刀盘损伤、掘进参数的波动、地面建筑不均匀沉降等风险,给施工带来一系列的挑战。针对房屋对变形敏感及孤石对掘进的不良影响,对土仓压力、刀盘扭矩、螺旋机输送速度、推力等掘进参数加以控制,辅以地面袖阀管注浆加固手段,保障土压平衡盾构机在孤石地层顺利下穿房屋,节约了大量成本。

After leaving Zhenlong South Station,the left tunnel of Zhenlongnan to Zhenlong undercrosss several buildings,which is mainly brick-concrete structure private houses with 2-5 layers. There are plenty of boulders within the scope of tunnel,which is mainly composed of granite fluvial soil and completely decomposed granites. A range of challenges were brought for construction because of risk of cutterhead damage,tunneling parameter fluctuation and differential settlement. Responding to the negative effects of settlement and boulder,the control of soil pressure,cutter torque,speed of screw conveyer and thrust,combined with grouting reinforcement of sleeve valve pipe has made. It enable EPB shield machine to cross buildings smoothly and yield significant savings.