中国首台单护盾TBM设备优化改造研究

甘肃省引洮供水一期工程总干渠7号隧洞围岩主要由上第三系Ⅴ类软-极软岩组成,采用单护盾TBM开挖掘进施工,针对围岩特性、设备运行状况与功能缺陷,以及遇到的各类问题,对设备主机机头刀盘及盾体进行了全面优化技术改造,并重点对盾体前伸护盾结构进行了三维有限元分析。施工实践表明:设备优化技术改造获得成功,技术性能得到全面提升,有效提升了施工效率、质量及安全,取得平均月成洞进尺1 094.0 m的优异成绩,创造了中国首台单护盾TBM在含水疏松粉细砂极软岩地层中的开挖掘进施工记录。可为各类盾构机的设计制造和工程运用提供良好借鉴。

Optimization reformation of China first single shield TBM

In the first stage construction of Taohe River Water Diversion Project in Gansu Province, the surrounding rock of No.7 tunnel mainly consists of Ⅴ class soft ~very soft rock of tertiary system, and the first single shield TBM in China was used to excavate the tunnel. According to the surrounding rock characteristics, equipment operation condition and function defects, the shield cutter head as well as the shield body were comprehensively optimized. Moreover, 3D finite element method was used to analyze the mechanical characteristics of the shield structure. The construction practice indicated that optimal reformation improved the construction efficiency and security. After optimization, the average excavation progress reached 1094.0m per month, creating a new record of the excavation by single shield TBM in water-contained loose fine sandy layer and the extremely soft rock layer.