Influence of Twin Tunnel Depth in Numerical Ground Movement Prediction Using Mohr Coulomb and Hardening Soil Model

Abstract

In urban area tunnel construction growing rapidly due to urbanization and increase in population rate. Tunnels are excavated at different depths from ground surface, but this will cause ground settlement in the excavation area which impact the surrounding structures. This paper is focused on effects of the surface ground movement prediction using numerical approach at various depth with Mohr Coulomb (MC) model and Hardening Soil (HS) model. Kenny Hill Formation used as the study area particularly chainage NB 1960. In this paper, the shape and pattern of the ground movement that obtained from simulation in PLAXIS 2D using MC model was compared with HS model output. Various tunnel depth location was used in the analysis such as real site condition tunnel depth and the relationship of 1d, 2d, 3d and 4d where d is the diameter of the tunnel. From this study, it can be seen that when tunnel depth increases the surface settlement decreases for both MC and HS model. But, the MC model’s ground surface settlements were undoubtedly lower than HS model.