Prediction of ground settlement induced by mechanized excavation in the Tehran Metro tunnel

The main issue of tunnelling in urban environment is the prediction of the ground settlements induced by tunnel excavation, which may cause damage to surface structures. In this paper are used empirical, analytical and three-dimensional finite element methods (by ABAQUS program) for the prediction of ground settlements induced during tunnel construction using EPB (earth pressure balance) excavation machine in part of the line 3 of Tehran subway. The results indicate that the three dimensional FEM predicts a more realistic surface settlement value, and settlement profiles from empirical and analytical methods are narrower than numerical one. Moreover, the maximum predicted settlement by three methods is more than its suggested allowable value.