Numerical Analysis Of Tunnelling In Sand - A Case Study Of A Centrifuge Test

Ground movement induced by TBM tunnelling in sand has been the subject of much discussion in recent years. It is commonly agreed that prediction of the ground movement trough in cohesionless soil is not easy. The main cause of ground movement in TBM projects is the tunnel volume loss induced by shield over-cutting and the dimensional difference between the shield and the lining. Numerical modelling could be a useful tool for ground movement prediction especially when dealing with projects where complex underground structures and strata distributions are involved. This paper employs the commercial FEM software Plaxis 3D in simulating of a centrifuge TBM tunnelling prototype using the constitutive model suggested by the software in analyzing behaviour of sands. Some popular empirical and analytical approaches of predicting ground movements are also adapted for the purpose of comparing with the numerical results.