TBM盾构机在上软下硬地层的施工技术研究
Research on Construction Technology of TBM Shield Machine in Upper Soft and Lower Hard Strata

上软下硬复合地层是盾构施工过程中的不良地层之一，对盾构的正常施工造成了比较大的影响。文章针对此类地层的主要特征，分析了在施工过程中造成滚刀偏磨、刀圈断裂的原因，并且从刀盘转速设计、使用硬度梯度刀圈和不同宽度的刀圈等方面提出了上软下硬复合地层盾构掘进施工方法，可为类似工程提供参考。
The upper-soft lower-hard composite stratum is one of the unfavorable strata in the shield construction process, which has a relatively large impact on the normal construction of the shield. In view of the main characteristics of such formations, this paper analyzes the reasons for the eccentric grinding of the hob and the fracture of the cutter ring during the construction process, and puts forward the above aspects from the design of the cutter head rotation speed, the use of the hardness gradient cutter ring and the cutter ring of different widths. The construction method of shield tunneling in soft-under-hard composite stratum can provide reference for similar projects.