Numerical Study of the Influence of Tunnel Excavation on Group Piles Using the Displacement Control Model

In urban environments, tunnels are often constructed in locations that are very closed to existing piles. Simple and reliable predictions of tunneling-induced bending moment and axial forces in pile foundations are important in safety of the tunneling. In this study, 3D numerical analysis by using finite difference software FLAC3D was done to investigate the effects of tunneling on pile foundation. The tunnel construction was simulated using Displacement control model (DCM). The numerical model was validated based on the results of a centrifuge test and a set of parametric study was carried out to assess the tunnel-group pile intraction. Simulation was indicated that tunneling-induced pile deformation and internal forces was mainly is related to pile tip situation. Comparison of single pile with front and rear piles show that the cap affects on pile deflection and internal forces

Keywords:

Tunneling , Group pile , Interaction , Displacement control model ,