水下盾构隧道施工渗流影响及加固措施分析

Analysis of seepage influence and reinforcement measures during underwater shield tunnel construction

依托福州地铁区间盾构隧道下穿潘墩河工程,结合数值模拟探讨盾构隧道在有无渗流因素影响下的围岩变形和塑性区分布,并提出相应的加固措施,最终研究成果表明:未考虑渗流的盾构施工产生的最大变形为0.88mm,考虑渗流后围岩变形增加23%,未考虑渗流的围岩塑性区范围相对较小,表明水下盾构隧道施工会对围岩位移产生较大影响;采用帷幕注浆加固后,围岩最大位移为0.65mm,表明帷幕注浆能降低渗流影响,减小围岩位移。

Relying on the Fuzhou Metro Interval Shield Tunnel Crossing Pandun River Project,numerical simulation was used to explore the surrounding rock deformation and plastic zone distribution of the shield tunnel with or without the influence of seepage factors,and corresponding reinforcement measures were proposed.The final research results showed that:The maximum deformation caused by shield tunnel construction considering seepage is 0.88 mm.After considering seepage,the deformation of the surrounding rock increases by 23%.The plastic zone of the surrounding rock without considering seepage is relatively small,indicating that the construction of underwater shield tunnel will cause displacement of the surrounding rock.Larger impact;after using curtain grouting for reinforcement,the maximum displacement of the surrounding rock is 0.65mm,indicating that curtain grouting can reduce the influence of seepage and reduce the displacement of the surrounding rock.The research results can provide reference for similar engineering cases of underwater shield tunnels.