以北京地铁19号线支线清河站南侧盾构区间为例，对盾构全水中接收各阶段工序、风险和控制参数进行分析，得出了相应的风险控制措施，并得到了成功应用。盾构全水中接收参数控制及监测数据表明：①全水中接收盾构井灌水高度在实测水位以上0.5m~1m，可有效控制盾构接收涌水涌沙情况；②接收期间土压力从15环的0.8~1.2bar逐渐降低为0bar，适当提高同步注浆量至理论值1.25倍，推进速度5.1mm/min，接近围护桩2环时推力从9000kN升至20000kN，磨桩期间推力在9000kN~14000kN，风险可控。③沉降发生主要有两个阶段，即刀盘出洞及盾尾脱出阶段，各占-0.9mm~-1.5mm，-4.0mm~-4.8mm，盾尾脱出影响大于刀盘出洞影响。

Based on the shield tunnel construction interval in the south side of Qinghe station of Beijing Metro Line 19 project, the procedures, risks and control parameters of each stage of the underwater receiving of shield machines were analyzed and the corresponding risk control measures were obtained and successfully applied. The shield parameters and monitoring results indicated that: when the height of filled water is 0.5m~1m above the ground water level, water and sand spewing can be effectively controlled. During the receiving period, the earth pressure gradually decreased from 0.8~1.2bar of the 15th ring to 0bar, the synchronous grouting amount was appropriately increased to 1.25 times of the theoretical value, and the advance speed was 5.1mm/min. When shield approaching the 2nd ring of the retaining pile, the thrust increased from 9000kN to 20000kN, and during the grinding pile period, the thrust was between 9000kN and 14000kN, and the risk was controllable. The settlement mainly occurred in two stages including the stage of cutter head coming out of the tunnel and the stage of shield tail coming out of the tunnel. The settlement values were in the range of -0.9mm~-1.5mm and -4.0mm~-4.8mm respectively. The influence of shield tail coming out of the tunnel was greater than that of cutter head coming out the tunnel.

北京市轨道交通建设管理有限公司双创基金