Influence of Tunnel Boring Machine (TBM) Advance on Adjacent Tunnel during Ultra-Rapid Underground Pass (URUP) Tunneling: A Case Study and Numerical Investigation

This study investigates the influence of subsequent tunnel boring machine (TBM)-driven processes on the responses of the first tunnel in twin-tunnel construction using the ultra-rapid underground pass (URUP) method. A comprehensive finite element analysis (FEA) is performed to simulate the URUP TBM tunneling, considering the non-uniform convergence caused by the TBM geometry, the tunnel face supporting pressure, and the tail-grouting pressure. The FEA model is validated by the monitoring results of the bending element of the first tunnel lining. The FEA results reveal that the grouting pressure of the second tunnel has significant influence on lining deformation of the first tunnel, while the face supporting pressure shows little effect. The relationship between the grouting pressure and the maximum bending moment of adjacent first tunnel can be fitted by linear function. A grouting pressure equals to the lateral earth pressure is able the reduce the variation of the bending element of the first tunnel during the TBM-driven process of the second tunnel. The bending element of the first tunnel shows a typical lognormal relationship with the face supporting pressure during the TBM advance of the second tunnel. A critical cover-to-depth ratio, under which the horizontal and vertical soil arching effect vanishes, can be deduced to be within the range of 0.55-0.60.

本研究利用超快速地下通道（URUP）法，探讨了后续隧道掘进机（TBM）驱动过程对双线隧道施工中第一条隧道响应的影响。进行了全面的有限元分析（FEA）以模拟URUP TBM隧道掘进，考虑了由TBM几何形状、隧道掌子面支护压力和壁后注浆压力引起的不均匀收敛。FEA模型通过第一条隧道衬砌弯曲元件的监测结果进行了验证。FEA结果表明，第二条隧道的注浆压力对第一条隧道的衬砌变形有显著影响，而掌子面支护压力影响较小。注浆压力与相邻第一条隧道的最大弯矩之间的关系可用线性函数拟合。等于侧向土压力的注浆压力能够减少第二条隧道TBM掘进过程中第一条隧道弯曲元件的变化。在第二条隧道TBM推进过程中，第一条隧道的弯曲元件与掌子面支护压力呈现典型的对数正态关系。可以推断出一个临界覆土深度比，在此比值下水平和垂直土拱效应消失，其范围在0.55 - 0.60之间。