水底隧道上软下硬地层超大直径盾构掘进技术难点与对策探讨

Analysis of Technical Difficulties and Countermeasures for the Super-Large Diameter Shield Tunneling in Upper Soft and Lower Hard Strata of Underwater Tunnel

为了解决水底软硬不均地层超大直径盾构施工技术问题,以某水底盾构隧道工程为依托,对超大直径盾构在水底上软下硬地层掘进中面临的技术难点、盾构机选型、施工方案选择、试验段掘进效果、方案可行性以及掘进管理控制等进行了分析和探讨。结果表明,采用有针对性设计功能的盾构机,在低刀盘转速、低掘进速度下,超大直径盾构直接掘进通过水底上软下硬地层的施工方案具有很高的可行性,并得到了成功实施。

In order to solve the technical problem of the super-large diameter shield tunneling in upper soft and lower hard strata of underwater tunnels,the technical difficulties,shield machine selection,the construction scheme comparison and selection,test section construction effect,construction scheme feasibility and construction management of which are analyzed,based on an underwater shield tunnel project.The results show that,under the condition of low cutter head speed and low tunneling speed,it is high feasible and has been implemented successfully for direct tunneling of super-large diameter shield machine with targeted design function through upper soft and lower hard strata underwater.