ABSTRACT

Two-dimensional (2D) model tests of tunnel excavation with corresponding numerical analyses were carried out to investigate fundamental mechanisms in ground behavior during tunneling. Numerical analyses were performed with the finite element method using the elastoplastic subloading tij model described in Section 6.2. Both model tests and numerical analyses were performed for two series of tunnel excavations. In the first series (series I), different tunnel depths were examined in order to investigate the influence of single tunnel excavation on surface settlement and earth pressure considering the ground as greenfield land (there is no structure on the ground surface above the tunnel).