Three-dimensional numerical analysis of corner effect of an excavation supported by ground anchors

This paper presents a case study and numerical simulations of a corner of a deep excavation in Tehran supported by soldier piles and ground anchors. This study focuses on the differences between 2D and 3D numerical modelling in estimating the wall deflection at the corner locations of the excavation. Furthermore, the performance of modelling with Mohr-Coulomb constitutive law was compared with the result of a hardening soil model. The modelling procedure was calibrated against a full-scale instrumented tieback wall at Texas A&M University and the monitoring data of the excavation project. The results indicated that the hardening soil model yields reasonable predictions of wall deflection in comparison to the Mohr-Coulomb model. Moreover, the 2D analysis overestimates the wall deflection near the corners. The 3D analysis shows that the closer each soldier pile to the corner, the lower the deflections of the soldier pile.