土压平衡盾构遭遇孤石、漂石的处理方法

Treatment of Boulders Encountered by Earth Pressure Balance Shield

以山西中部引黄工程盾构施工区间为例,就其在掘进过程中突遇未探明的孤石、大直径漂石,造成了盾构卡机无法继续推进以及在原有盾构机选型和刀具配置均不能适用于坚硬孤石地层的情况,采用“地震散射+物探验证”的探测方法确定了孤石、漂石的位置,通过对比后选用了潜孔钻机密打孔的方式将孤石、漂石打成筛状。同时,通过更换刀具也增强了盾构刀盘对该种复合地层的适用性。运用上述处理方法后,盾构机顺利通过了孤石、漂石段,使隧道成功贯通。通过对比分析地震散射探测报告与验证取芯数据,证明了地震散射技术探测孤石、漂石分布状态和位置的有效性;通过对比盾构恢复推进前后的各项参数,证明了潜孔钻机密打孔是一种效率高、成本低、风险低的孤石、漂石处理方法,该方法也可为类似工程提供参考。

The shield construction section of the Yellow River Diversion Project in Central Shanxi was taken as an example.During the tunneling process,the unproved boulders and large-diameter boulders encountered made the shield jam and could not advance,and the original shield machine selection and tool configuration cannot be applied to the hard boulder formation so that the detection method of“seismic scattering+geophysical exploration verification”was applied to determine the location of boulders and boulders.After comparison,the boulders and boulders were drilled into sieve by close punching of down-hole drill.That changing the tool enhanced the applicability of the shield cutter head to the composite stratum.After the treatment,the shield machine successfully passed through the boulder and boulder sections and obtained the tunnel through.Through the comparison and analysis of seismic scattering report and verification core data,the effectiveness of seismic scattering technology in detecting the distribution and location of boulders is proved;Comparing the parameters before and after the resumption of the shield,it is proved that the close punching with down the hole drill is high efficiency,low cost and low risk treatment for boulders,which can provide a reference for similar projects.