Numerical Simulation of EPB Shield Tunnelling with TBM Operational Condition Control Using Coupled DEM–FDM

This study demonstrates a three-dimensional numerical simulation of earth pressure balance (EPB) shield tunnelling using coupled discrete element method (DEM) and finite difference (FDM). The analysis adopted the actual size spoke-type EPB tunnel boring machine (TBM) consisting cutter head with cutting tools, working chamber, screw conveyor, shield. For model to reproduce in situ ground condition, formation was generated partially DEM (for limited domain influenced by excavation), rest being composed FDM grids. In domain, contact parameters particles were calibrated via series large-scale triaxial test analyses. simulated as TBM operational conditions controlled. penetration rate rotational speed conveyor automatically adjusted advanced prevent generation excessive or insufficient torque, thrust force, chamber pressure. Accordingly, these maintained consistently around their set ranges during excavation. results show that proposed based on DEM–FDM coupling could reasonably simulate driving while considering conditions.